MTO with RM stock maintained

Dear all Hi,

I have certain stock of RM's maintained in plant & production will happen only after creation of sale order subsequent execution of MRP, but every MRP run will trigger a PR for that RM rather than Just reserving the material from the available stock, please suggest what should be done to restrict the system to generate reservations if naterial is available & it should trigger PR's if there is short or no stock of RM. Is there any strategy for this situation.

Thanks in advance.