TOPIC: How are warranties handled in the closing process

I am unclear about closing a procurement or closing a project when the project product has a warranty that the seller must contractually provide. On one hand, the warranty is a supplemental deliverable and a "contractual obligation" which would not have been fulfilled. On the other hand, the product itself would be transferred to the customer and the warranty would appear to be more operational in nature than project. How do we handle this? Thank you