Exhibit 23.1



CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the  incorporation  by reference in  Registration  Statement  Nos.
333-119474 and 333-40472 of KeySpan  Corporation on Form S-8 of our report dated
June 22, 2006,  appearing in this Annual  Report on Form 11-K of KeySpan  Energy
401(k) Plan for Management Employees for the year ended December 31, 2005.

/s/ Deloitte & Touche LLP
New York, New York


June 22, 2006












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