Exhibit 23-a Consent of Arthur Andersen, LLP, Independent Accountants
CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS
As independent public accountants, we hereby consent to the incorporation by
reference in this registration statement, as amended (Registration No.
333-53657) of our report dated January 27, 2000 included in KeySpan
Corporation's Form 10-K for the year ended December 31, 1999.
/s/ Arthur Andersen LLP
ARTHUR ANDERSEN LLP
New York, New York
December 11, 2000
II-11
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Exhibit 23-b Consent of Ernst & Young LLP, Independent Auditors
CONSENT OF INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts" in the
Post-Effective Amendment No. 1 to the Registration Statement (Form S-3 No.
333-53657) of KeySpan Corporation and to the incorporation by reference therein
of our report dated May 22, 1998, with respect to the financial statements and
schedule of Long Island Lighting Company included in the Annual Report (Form
10-K) of KeySpan Corporation (formerly known as MarketSpan Corporation) for the
year ended December 31, 1999, as amended, filed with the Securities and Exchange
Commission.
/S/ ERNST & YOUNG LLP
ERNST & YOUNG LLP
December 13, 2000
Melville, New York
II-12
