Payables payments link to Trade Management

Hi,

If payables receives and processes an invoice related to a Trade Management promotion or budget, how does the Trade Management budget get correctly lowered due to the expense?  I understand that a claim can now be settled by a 'Check' method but sometimes we make payments that need to be funded out of the promotional budget because the earned discount can be used to pay for a wide variety of activities related to that customer or item and promotion.

Thanks,

Jason