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 (Registration No. 333-43768) of our
report dated January 27, 2000 included in KeySpan Corporation's Form 10-K for
the year ended December 31, 1999. We also hereby consent to the incorporation by
reference in the registration statement of our report dated January 21, 2000,
appearing in the Annual Report on Form 10-K of Eastern Enterprises for the year
ended December 31, 1999.
/s/ARTHUR ANDERSEN LLP
New York, New York
October 13, 2000
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Exhibit 23-b Consent of Ernst & Young LLP
CONSENT OF INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts" in the
Registration Statement, as amended, (Form S-3 Registration No. 333-43768) and
the related Prospectus of KeySpan Corporation for the registration of
$1,650,000,000 of debt securities 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), as amended, of KeySpan Corporation (formerly known as MarketSpan
Corporation) for the transition period from April 1, 1998 to December 31, 1998,
filed with the Securities and Exchange Commission.
/s/ERNST & YOUNG LLP
Melville, New York
October 13, 2000
