Travel and Expense Module link with Procurement and Sourcing

Workers are filling out travel requisitions before they travel, one of the expense lines is ( Flight ) for which we need to submit a "Purchase Requisition" and get three offers from three different suppliers ..

How to automate this using the standard functionality of the system. Is there a way to link "Travel and Requisition" and "Purchase Requisitions / Orders " ?

Thanks in Advance,