March 31, 2006

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                            SCHEDULE 14A INFORMATION
                                 (Rule 14a-101)

                  Proxy Statement Pursuant to Section 14(a) of
            the Securities and Exchange Act of 1934 (Amendment No. )

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Filed by a Party other than the Registrant  [ ]

Check the appropriate box:
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        Rule 14a-6(e)(2))
[ ]     Definitive Proxy Statement
[ ]     Definitive Additional Materials
[X]     Soliciting Material Pursuant to Section 240.14a-12

                              KeySpan Corporation
                              -------------------
                (Name of Registrant as Specified in Its Charter)

                                     (N/A)
                                     -----
    (Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

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(2)  Aggregate number of securities to which transaction applies:
     N/A______________________________________________________________

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     to Exchange  Act Rule 0-11 (set forth the amount on which the filing fee is
     calculated and state how it was determined):
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(4)  Proposed maximum aggregate value of transaction:
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Communication #1

Attached is a script of the testimony that Robert B. Catell,  Chairman and Chief
Executive  Officer  of  KeySpan  Corporation  ("KeySpan")  prepared  for  a  the
Planning, Development and Environment Committee of the Nassau County Legislature
hearing on Friday,  March 31, 2006 which addressed the acquisition of KeySpan by
National Grid:












                          Testimony of Robert B. Catell
                                Chairman and CEO
                               KeySpan Corporation

                                     Before

               The Planning, Development and Environment Committee
                        Of the Nassau County Legislature

                                       On

   "What effect will the sale of KeySpan have on Long Island's energy supply,
                             generation and rates?"


                             Friday, March 31, 2006





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o    Good  afternoon.  My name is Robert  Catell,  and I am Chairman  and CEO of
     KeySpan  Corporation.  It's my great pleasure to be here with my colleague,
     Michael Jesanis, CEO of National Grid's U.S. Division.

o    I want to thank  Committee  Chairman David  Denenberg for inviting me here,
     and thank the other members of the committee.

o    I also want to thank the  Legislatures  on Long Island for spending time on
     such an important subject:  National Grid and KeySpan,  and the impact that
     transaction will have for Long Island.

o    As you know,  KeySpan has entered into an agreement with National Grid that
     will spell an  exciting  new chapter in both our company and energy on Long
     Island.

o    This story began in 1998, when a company called KeySpan came to Long Island
     to turn a local utility called LILCO into what I think everyone would agree
     is a stronger, more well-regarded organization.

o    Today's KeySpan is financially  sound, has a strong community  presence and
     continues  to  provide  the  highest  levels of service  with an  extremely
     dedicated and qualified work force, most of whom live on Long Island.

o    There's a similar  story that  played out in a similar  way about six years
     ago, when a company  called  National Grid acquired a financially  troubled
     Niagara  Mohawk,  or NIMO,  in  upstate  New  York.  Today,  that  National
     Grid-owned business is financially robust, with a good corporate reputation
     and a strong community commitment.

o    Soon, KeySpan will become part of National Grid's success story - part of a
     larger company that will give us access to more resources to make even more
     of a difference in the communities we serve.

o    Some people claim that foreign  ownership isn't a good thing.  But I'd like
     you to look  at the  example  of  European  American  Bank,  or  EAB.  This
     financial institution took over financially troubled Franklin National Bank
     back in 1974, and went on to serve and benefit Long Islanders for more than
     a quarter-century.

o    Also consider this: While National Grid is London-based,  55 percent of its
     operations are right here in the U.S. and KeySpan,  its fifth  acquisition,
     is by far its largest.

o    Together,  National  Grid and KeySpan  will be able to play a major role in
     energy issues around the globe; issues affect us right here on Long Island,
     too - like  ensuring  reliability  while we trim our  operating  costs  ...
     keeping  rates stable or lower ...  ensuring  adequate gas supplies ... and
     the list goes on.


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o    But let's look closer to home. Richie Kessel has also been testifying about
     the National Grid/KeySpan transaction, and its potential effect on LIPA and
     Long Island.

o    As you all know,  KeySpan and LIPA entered into a very favorable  agreement
     for  customers  in  December.  It  includes a two-year  rate freeze ... $38
     million  in  operating  cost  reductions  ... a $75  million  fuel  fund to
     mitigate increased fuel costs ... and incentives for continued  reliability
     and  stability to LIPA's 1.1 million  electric  customers  through the year
     2013.

o    KeySpan is committed to this agreement and the benefits it provides, and we
     will work hard in the coming months to see this  contract  approved to make
     sure these  benefits  remain intact.  Once approved,  National Grid will be
     bound by all the terms of that agreement.

o    KeySpan will also continue to advance repowering  alternatives with LIPA as
     part of a long-range environmental plan for Long Island.

o    As part of the recent  agreement,  LIPA has the  opportunity to acquire the
     Far Rockaway and Barrett  Plants,  which are among the least  efficient and
     most suitable units for repowering.

o    And we stand  ready to build a new  combined-cycle  plant at the  permitted
     site on Spagnoli  Road,  the perfect  location:  It's in the center of load
     growth,  a mile from  existing  gas supply and just a mile from the nearest
     substation.  Building  Spagnoli would accomplish a "virtual  repowering" as
     the  high-efficient  new plant would mean our older plants,  like Glenwood,
     would run less.

o    Our  Article X permit is in place;  we have an  agreement  with the Town of
     Huntington;  engineering  is done;  the site is ready to go. All we need is
     LIPA's agreement to go forward.

o    In addition to  repowering,  we will also continue to explore and invest in
     emission  reduction  technologies  at all of our plants.  These  plants are
     still among the cleanest in the country;  however,  there's more we will do
     to make them even cleaner, and more fuel-efficient and cost-effective.

o    So as we enter into this  agreement with National Grid, we will continue to
     pursue all of these things ... plus we stand firmly  committed to providing
     top-notch service to our customers and communities here on Long Island.


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o    And that better service will result from five key benefits of the deal that
     I'd like to put on the record today. It will allow us to :

o    1. provide consumers with lower energy delivery costs

o    2.  invest in new,  secure  sources of supply  and  energy  infrastructure,
     critical to Long Island

o    3. achieve the scale necessary to achieve fuel cost savings

o    4. utilize advanced, efficient technologies that benefit both customers and
     the environment; and

o    5. ultimately, grow, in an increasingly complex, competitive environment.

o    Until the National Grid/KeySpan deal receives final regulatory approval, of
     course,  we are  committed to ensuring as smooth a transition  as possible;
     one that will be seamless to our customers and the community.

o    I, in  fact,  will be  staying  on as  Chairman  of  National  Grid's  U.S.
     Division,  and serving on the Board and as Deputy  Chairman of London-based
     National Grid plc for at least two years after the deal closes.

o    During that time, I will make it my personal  commitment to ensure that our
     company  continues to forge solid -- and sustainable -  relationships  with
     all the people we interact and conduct business with.

o    And I'd like to now introduce you to another person who is committed to the
     success of our new company and the interests of Long Island - my colleague,
     Mike Jesanis, CEO of National Grid's U.S. Operations.

o    After  Mike  offers  some  brief  remarks,  we will  open the floor to your
     questions.



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Communication #2

Attached  is a script  of the  testimony  that  Michael  E.  Jesanis,  Chairman,
National  Grid's U.S.  Division  prepared for a the  Planning,  Development  and
Environment  Committee of the Nassau County Legislature hearing on Friday, March
31, 2006 which addressed the acquisition of KeySpan by National Grid: o




                         Testimony of Michael E. Jesanis
                                    Chairman
                          National Grid's U.S. Division

                                     Before

               The Planning, Development and Environment Committee
                        Of the Nassau County Legislature

                                       On

   "What effect will the sale of KeySpan have on Long Island's energy supply,
                             generation and rates?"


                             Friday, March 31, 2006




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o    Good afternoon everyone.  I'm delighted to be with all of you, here on Long
     Island.  As Bob  mentioned,  this  is a  community  that we are  very  much
     committed to serving in the best ways possible.

o    And I've already had a great  opportunity to see that KeySpan is, indeed, a
     respected provider, employer and corporate citizen on Long Island.

o    So the job of our new company,  as I see it, is to continue  the  excellent
     service and reliability record KeySpan has so successfully established.

o    That means continuing to provide the top-level  service Long Islanders have
     come to expect, and we're all committed to doing just that.

o    It means  continuing the strong  community  commitment  that has so clearly
     been a KeySpan trademark.

o    And it means taking the opportunity to enhance customer service.  And there
     are three great ways we'll be able to accomplish that.


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o    One, we'll have a larger work force, which means more internal resources to
     meet our needs, especially in emergency situations.

o    Two, we'll have greater  access to capital  resources to invest in exciting
     new technologies and R&D, as Bob mentioned.

o    And three,  we'll be able to operate more efficiently - which means synergy
     savings that can benefit both shareholders and ratepayers.

o    So it's an  exciting  proposition.  And I'm as  happy as Bob is that he has
     agreed to stay on as  Chairman of National  Grid's U.S.  Division,  where I
     know he'll assure as smooth a transition as possible.

o    Bob really  covered a lot already,  but I just want to touch on a couple of
     things briefly.  First,  KeySpan's  relationship with the Long Island Power
     Authority.

o    This is a very  important  relationship,  and it's a unique  public/private
     partnership  that has served the Long Island  community  well over the past
     eight years.


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o    National  Grid has had the pleasure of meeting with LIPA over the past year
     and has  started  to form  its  own  solid  relationship  with  the  public
     authority.   And  we  are  looking   forward  to  continuing  that  working
     relationship with Richard Kessel, LIPA and New York State, as LIPA conducts
     due  diligence  and explores its options  moving  forward.  In fact, we are
     already in the midst of  developing  some joint,  storm season  initiatives
     that we will be discussing with LIPA.

o    We've also been kept  apprised on the progress  and benefits of  repowering
     ... and look  forward to  continuing  to pursue the best  options  for Long
     Island in this critical area which shows a great deal of merit.

o    As Bob said,  we are  committed,  too,  to being a strong  presence on Long
     Island and in the other  communities  we serve - a hallmark of both KeySpan
     and National  Grid.  And we have, in fact,  pledged to maintain the current
     community commitment level here.


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o    We're also dedicated to our employees, another trademark of both companies.
     And let me assure  you that  National  Grid is  counting  on Long  Island's
     excellent,  highly  qualified and trained work force to continue to provide
     great service and reliability.

o    And, as we have always done in the past, we are treating  this  acquisition
     as more of a merger, and will achieve synergy savings through attrition and
     voluntary separation.

o    In short,  we recognize that the  KeySpan/National  Grid  transaction  must
     provide a few key elements.

o    It must have a  neutral  or  positive  impact  on  rates,  something  we've
     accomplished in each of our four previous mergers and plan to do now.

o    It must benefit consumers and it will in ways Bob mentioned.

o    And, of course,  we will be working with the PSC regarding our relationship
     with LIPA and the impact of the deal on LIPA customers.

o    Finally, we plan to maintain, and even improve upon, both of our companies'
     solid performance records with the benefit of additional efficiencies, cost
     savings and technologies.

o    Thank you and now, as Bob said, we welcome your questions.


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Additional Information and Where to Find It
- -------------------------------------------

KeySpan intends to file with the Securities and Exchange  Commission (the "SEC")
a proxy  statement and other relevant  documents in connection with the proposed
acquisition  of KeySpan by National  Grid.  Investors  and  security  holders of
KeySpan are advised to read the proxy  statement  and other  relevant  documents
when they become available, as they will contain important information about the
transaction.  Investors and security holders may obtain a free copy of the proxy
statement  and other  documents  filed by KeySpan with the SEC, when they become
available, at the SEC's web site at http:/www.sec.gov.

KeySpan  and  its  directors,  executive  officers  and  other  members  of  its
management and employees may be deemed to be participants in the solicitation of
proxies from its security  holders in connection with the proposed  acquisition.
Information   concerning  the  interests  of  KeySpan's   participants   in  the
solicitation  is set forth in KeySpan's  most recent proxy  statement and Annual
Report on Form 10-K (filed with the SEC on March 30, 2005 and February 28, 2006,
respectively)  and will be set  forth in the  proxy  statement  relating  to the
acquisition when it becomes available.





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