In a divorce action, the defendant appeals from an order of the Supreme Court, Rockland County (Daronco, J.), entered September 9, 1980, which denied his motion to dismiss the second cause of action for legal insufficiency. Order reversed, on the law, without costs or disbursements, and defendant’s motion granted. Absent factual allegations in plaintiff’s second cause of action demonstrating that because of either mutual mistake, mistake and fraud, or inherent ambiguity, the separation agreement fVied to express the intent of the parties concerning child support, it was insufficient on its face to state a cause of action for child support “in accordance with the financial circumstances of the defendant by modifying the support provisions of the Separation Agreement dated July 16,1975” (emphasis supplied). Where, as here, the plaintiff seeks a direction in the judgment of divorce for child support in excess of the amount provided for in the separation agreement by reason of unanticipated change in circumstances and the concomitant need of the child, such relief may be applied for, as an incident of the divorce action, by motion on notice upon plaintiff’s affidavit containing a factual showing that since the execution of the separation agreement there has been “an unanticipated and unreasonable change in circumstances” showing a need on the part of the child (Matter of Boden v Boden, 42 NY2d 210, 213). Upon such application, contrary to the determination of Special Term, the burden of proof is upon the plaintiff to establish that the provisions for child support contained in the separation agreement are inadequate to furnish the daily needs of the child, that the defendant’s present financial circumstances have substantially improved since the time when the agreement was made, and that an appropriate increase in child support should be' directed in the judgment, pursuant to.subdivision 1 of section 240 of the Domestic Relations Law (see Pournaras v Pournaras, 75 AD2d 546). Mangano, J.P., Gibbons, Cohalan and O’Connor, JJ., concur.