President Donald Trump said Amazon Inc. should pay higher prices for shipping packages to cover the cost of the U.S. Postal Service.

“Amazon is going to pay for the post office,” Trump said Tuesday during a visit to Yuma, Arizona, repeating a false claim that the postal service loses money on Amazon shipments because of negotiated rates.

“It’s part of their model. They think the post office is stupid,” Trump said of the company.

The Postal Service has been at the center of a political firestorm after Trump directly tied his opposition to a proposed $25 billion financial lifeline to his criticism of efforts to encourage mail-in voting during the coronavirus pandemic.

Postmaster General Louis DeJoy said earlier Tuesday that he is suspending changes to mail service that raised concerns over slow delivery of ballots in the fall election after Democrats accused Trump of hampering the vote-by-mail process.