U.S.-based investment companies Blackstone and Centerbridge are considering a 3 billion euro ($3.5 billion) offer for Spanish lender Banco Santander’s headquarters (HQ) in Madrid.

A deal would extend Blackstone’s presence in Spain, which is enjoying an economic rebound.

Blackstone is in talks with Centerbridge about a joint offer and the bid might be submitted next week.

In August last year, Centerbridge bought control of property worth $11 billion from Santander.