In an action arising from an alleged breach of a subscription agreement for the purchase of a cooperative apartment, the defendants appeal, as limited by their brief, from so much of an order of the Supreme Court, Richmond County (Leone, J.), dated July 8, 1988, as, upon denying their motion to vacate a preliminary injunction, did not require the plaintiffs to file an undertaking pursuant to CPLR 6312 (b).
*708Ordered that the order is reversed insofar as appealed from, with costs, and the matter is remitted to the Supreme Court, Richmond County, for a determination of the amount of the undertaking to be filed by the plaintiffs pursuant to CPLR 6312 (b).
We agree with the defendants that the Supreme Court erred by declining to require the plaintiffs to file an undertaking as mandated by CPLR 6312 (b) (see, Ziankoski v Simmons, 140 AD2d 1007; see also, Feeley v Midas Props., 154 AD2d 505; Mr. Natural, Inc. v Unadulterated Food Prods., 152 AD2d 729). In light of the foregoing, we remit the matter to the Supreme Court, Richmond County, for a determination of the amount of the undertaking to be filed. Mangano, J. P., Brown, Kooper and Harwood, JJ., concur.