Stamford‑based Webster Bank is set to become part of a larger banking operation under a new acquisition agreement announced today.

Banco Santander said it has entered into an agreement to acquire Webster Financial Corporation, the holding company for Webster Bank.

Santander said the deal will create a stronger and more competitive bank for customers.

Santander said the acquisition will significantly expand its scale, deposit base and capabilities in the United States.

Santander said, until the transaction closes, Santander and Webster will continue to operate as separate companies, and there will be no changes to Santander or Webster customer accounts, branch access or day-to-day service.

The transaction represents about 4% of Santander’s total assets, the company said.