DECISION ORDER
ORDERED that the order is affirmed insofar as appealed from, with one bill of costs to the respondents appearing separately and filing separate briefs.
It is well settled that "[a] failure by the insurer to give [notice of disclaimer] as soon as is reasonably possible after it first learns of the accident or of grounds for disclaimer of liability or denial of coverage, precludes effective disclaimer or denial" (Hartford Ins. Co. v. County of Nassau, 46 N.Y.2d 1028, 1029 ; see, Matter of State Farm Mut. Auto. Ins. Co. v. Cote, 200 A.D.2d 622, 623 ; New York Cent. Mut. Fire Ins. Co. v. Markowitz, 147 A.D.2d 461, 462 ). This rule applies even where, as here, the insured failed to provide the carrier with timely notice of the claim in the first instance (see, Matter of State Farm Mut. Auto. Ins. Co. v. Cote, supra, at 623; Kramer v. Interboro Mut. Indem. Ins. Co., 176 A.D.2d 308 ). Where the ground for disclaiming coverage should have been readily apparent to the carrier when it first received notice of the claim, the requirement for timely notice is particularly applicable (see, Matter of Nationwide Mut. Ins. Co. v. Steiner, 199 A.D.2d 507 ; Kramer v. Interboro Mut. Indem. Ins. Co., supra). It is the responsibility of the insurer to explain the delay (see, Hartford Ins. Co. v. County of Nassau, supra, at 1029-1030).
In the instant case, four months after receiving notification of the plaintiffs' claim for uninsured motorist benefits, New York Central Mutual Fire Insurance Company (hereinafter New York Central) notified the plaintiffs that it was disclaiming coverage on the ground that the notice of claim was untimely filed. No explanation was offered by New York Central to justify its four-month delay in notifying the plaintiffs of its disclaimer. Under these circumstances, and given that the primary reason for disclaiming coverage was readily apparent upon receipt of notice of the claim, New York Central's unexplained delay in disclaiming coverage was unreasonable.