Cancelation of Purchase Order - Contractual liability of the vendor.

Can a vendor be held liable for contractual violation when he cancels purchase orders after initial approval, and based on that the supplier has already procured the required goods.?
The vendor has canceled the order after all the required goods as per the purchase order have been procured by the supplier. And now the supplier is facing losses with the dead stock in a warehouse. The parties did not have a formal contract as they have trusted business relations since a decade.
Kindly Advise suitable remedy.