WASHINGTON — Senators are urgently trying to save the struggling U.S. Postal Service after its announcement that it will cut Saturday delivery starting in August.

In a hearing Wednesday before the Senate Homeland Security and Governmental Affairs Committee, senators and post office advocates agreed on the importance of immediate congressional changes to the Postal Service’s operations, though there was no agreement on the specifics of how to do so.

Postmaster General Patrick R. Donahoe urged Congress to allow the agency to form its own health-care plan and not restrict the agency in its move to a five-day delivery week. A new system in which the Postal Service managed its own health care for employees and switched to a new business model could save up to $7 billion by 2016, he said.