May 30, 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. )

Filed by the Registrant  [X]
Filed by a Party other than the Registrant [ ]

Check the appropriate box:
[ ]     Preliminary Proxy Statement
[ ]     Confidential, For Use of the Commission Only (as permitted by
        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)

Payment of Filing Fee (Check the appropriate box):
[X]     No fee required.
[ ]     Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

(1)  Title of each class of securities to which transaction applies:
     N/A______________________________________________________________
(2)  Aggregate number of securities to which transaction applies:
     N/A______________________________________________________________
(3)  Per unit price or other underlying value of transaction  computed  pursuant
     to Exchange  Act Rule 0-11 (set forth the amount on which the filing fee is
     calculated and state how it was determined):
     N/A______________________________________________________________

(4)  Proposed maximum aggregate value of transaction:
     N/A______________________________________________________________
(5)  Total fee paid:
     N/A______________________________________________________________






[  ] Fee paid previously with preliminary materials.
[  ] Check box if any part of the fee is offset as provided by Exchange Act Rule
     0-11(a)(2)  and identify the filing for which the  offsetting  fee was paid
     previously.  Identify the previous filing registration statement number, or
     the Form or Schedule and date of its filing.

(1)  Amount Previously Paid:
     N/A______________________________________________________________
(2)  Form, Schedule or Registration Statement No.:
     N/A______________________________________________________________
(3)  Filing Party:
     N/A______________________________________________________________
(4)  Date Filed:
     N/A______________________________________________________________












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The following  communication  is being  distributed  to all KeySpan  Corporation
("KeySpan")  and National Grid employees and will be posted on their  respective
internal websites.

Integration Update

Volume 1, Issue 7


May 26, 2006


                          FERC MERGER APPLICATION FILED
             Combination of companies will satisfy FERC regulations

As a next important step in moving our  integration  forward,  National Grid and
KeySpan  filed a joint  application  yesterday  with  the  U.S.  Federal  Energy
Regulatory Commission (FERC), seeking approval of the proposed merger of the two
companies. The filing, required by FERC statute, states the merger is consistent
with the public  interest  and  addresses  key  concerns  of the FERC in similar
transactions.

In addition to providing the  documentation  and information  required by FERC's
regulations,  the application  demonstrates  how the merger will have no adverse
impact on wholesale competition.  Also, the filing describes how the merger will
cause no adverse impact on transmission and regulated  wholesale  customer rates
or on regulation.  The merger will also not result in  cross-subsidization  from
regulated operations to unregulated operations.  The analysis of the competitive
impacts of the merger was done by an independent  economist  using the framework
required by FERC.

FERC  approval is required for the  transaction  to close,  estimated  for early
2007. The application requests a FERC decision by late October.

Future Updates
We will continue to keep you informed of the team's progress through Integration
Update, the integration intranet sites and face-to-face  communications.  If you
have questions at any time, please feel free to contact your sub team leads; use
the Integration  Hotlines at  1-800-523-1044  (National Grid) or  1-888-698-4397
(KeySpan);       or      e-mail       IntegrationQuestions@us.ngrid.com       or
IntegrationQuestions@keyspanenergy.com.





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

KeySpan intends to file with the Securities and Exchange  Commission (the "SEC")
a definitive proxy statement and other relevant documents in connection with the
proposed  acquisition of KeySpan by National Grid. We filed a preliminary  proxy
statement  with the SEC on April 28, 2006.  Investors  and  security  holders of
KeySpan are advised to read the proxy  statementd 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  Annual  Report on Form 10-K (filed with
the SEC on  February  28,  2006),  Quarterly  Report on Form 10-Q for the period
ended March 31, 2006, KeySpan's  preliminary proxy statement (filed with the SEC
on April  28,  2006)  and will be set forth in the  definitive  proxy  statement
relating to the acquisition when it becomes available.








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