How to accrue two way matched PO's

Hi All,

We are PO's which are two matched i.e. there is no PO receipt.

Ex:- PO is for say 120,000 for services to be rendered by Vendor for entire Financial year. As and when AP invoice is sent by Vendor, the same is being entered in AP and hence Expense account gets a hit, but in those months where there is no AP invoice sent by Vendor, is there a way where users can set the accrual amount and system should generate Accrual entries in GL on the last day of the month?

Regards,

Arvind