OPINION OF THE COURT

Memorandum.

The order of the Appellate Division should be affirmed, with costs.

In these circumstances, the Appellate Division correctly concluded that plaintiff may maintain an action on the parties’ separation agreement. Defendant, in his answer, did not dispute the validity of the agreement, and therefore is deemed to have admitted it (CPLR 3018, subd [a]). He may not now be heard to complain that the contract is no longer in existence. In so ruling, we intimate no view on the question whether defendant could collaterally attack the clause in the divorce *1011 decree which provided for survival of the separation agreement.

Chief Judge Cooke and Judges Jasen, Gabrielli, Jones, Wachtler, Fuchsberg and Meyer concur.

Order affirmed, with costs, in a memorandum.