*866The 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. of Sullivan County v Scheinman, 53 NY2d 12, 16 [1981]). In addition, “[b]ecause 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 [1988]; see Matter of Rush v Mordue, 68 NY2d 348 [1986]). The petitioner has failed to demonstrate a clear legal right to the relief sought. Balkin, J.E, Dickerson, Leventhal and Lott, JJ., concur.