*778"Because of its extraordinary nature, prohibition is available only where there is a clear legal right, and then only when a court — in cases where judicial authority is challenged — acts or threatens to act either without jurisdiction or in excess of its authorized powers” (Matter of Holtzman v Goldman, 71 NY2d 564, 569; see, Matter of Rush v Mordue, 68 NY2d 348, 352). Similarly, the extraordinary remedy of mandamus will lie only to compel the performance of a ministerial act, and only when there exists a clear legal right to the relief sought (see, Matter of Legal Aid Socy. v Scheinman, 53 NY2d 12, 16).
The petitioner has failed to demonstrate a clear legal right to the relief sought. O’Brien, J. P., Ritter, Hart and Goldstein, JJ., concur.