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                                                               Exhibit 10.20(b)
                                SECOND AMENDMENT
                            TO SECONDMENT AGREEMENT

THIS AGREEMENT is made the first day of October, 1996 

BETWEEN:

(1)  NYNEX CableComms Limited, (registered in England, No. 2664006) whose
     registered office is at The Tolworth Tower, Ewell Road, Surbiton, Surrey
     KT6 7ED (the "Company"); and 

(2)  NYNEX Worldwide Services Group, Inc., a company incorporated under the laws
     of the State of Delaware, with its principal place of business at 1113
     Westchester Avenue, White Plains, New York 10604, USA ("WSG"),

WHEREAS:

(1)  The parties have entered into a Secondment Agreement dated May 15, 1995 and
     modified by the First Amendment to Secondment Agreement dated December 7,
     1995 (together, the "Secondment Agreement") under which WSG has agreed to
     make available to the Company the services of JOHN F. KILLIAN (the
     "Employee") for the consideration and subject to the terms and conditions
     of the Secondment Agreement; and

(2)  The parties hereto wish to modify the terms of the Secondment Agreement:

IT IS HEREBY AGREED as follows:

1.   Effective 1 October, 1996, Clause 4(B) is amended by adding the following
     plan to the end of the section entitled "Senior Management Programs":

                    NYNEX 1987 Restricted Stock Award Plan.


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2.   Save as modified herein, the provisions of the Secondment Agreement shall
     continue in full force and effect.



SIGNED BY PAUL REPP for and          )          /s/ Paul Repp             
on behalf of NYNEX CABLECOMMS        )
LIMITED in the presence of:          )          /s/ Richard W. Blackburn

SIGNED BY R.W. BLACKBURN for and     )          /s/ Richard W. Blackburn   
on behalf of NYNEX WORLDWIDE         )
SERVICES GROUP, INC. In the          )
presence of:                         )          /s/ Paul Repp