Shareholder circular

National Grid PLC
28 June 2006


                                                                    28 June 2006

                               National Grid plc
Shareholder Circular - Proposed Acquisition of KeySpan Corporation and Notice of
                         Extraordinary General Meeting

The Board of National Grid plc announced on 27 February 2006 that they had
signed a Merger Agreement under which National Grid will acquire KeySpan
Corporation, a major energy delivery company in the northeastern US (the 
'Proposed Acquisition').

Approval for the Proposed Acquisition will be sought from National Grid
shareholders through an ordinary resolution at the Extraordinary General Meeting
of National Grid plc to be held at 2.15 p.m. or, if later, immediately following
National Grid's Annual General Meeting, on 31 July 2006 at The ICC, Birmingham.

A Circular containing further information on the Proposed Acquisition and Notice
of Extraordinary Meeting is being posted to shareholders.

Copies of the Circular are available for inspection at the UK Listing
Authority's Document Viewing Facility, which is located at:

UK Listing Authority
Financial Services Authority
25 The North Colonnade
Canary Wharf
London
E14 5HS
Tel: [phone]

The Circular will also be available on National Grid's website at
www.nationalgrid.com/corporate.

Enquiries:

National Grid
Investors

Dave Campbell             [phone]
Richard Smith             [phone]
James Waite               [phone]

Media

Clive Hawkins             [phone]


Citigate Dewe Rogerson    [phone]

Anthony Carlisle          [phone]


Deutsche Bank AG London, Joint Sponsor to National Grid

James Agnew               [phone]
Martin Pengelley          [phone]


Morgan Stanley & Co. Limited, Joint Sponsor to National Grid

Alisdair Gayne            [phone]
Alastair Cochran          [phone]




                      This information is provided by RNS
            The company news service from the London Stock Exchange