WASHINGTON (AP) — President Donald Trump said Wednesday he is considering buying used Boeing aircraft — perhaps from an overseas seller — to use as Air Force One when he’s aboard, as he fumes over the U.S. plane-maker’s delays in producing two specially modified ones for presidential use.

Air Force One is a modified Boeing 747. Two exist and the president flies on both of the more than 30-year-old planes. Boeing has the contract to produce updated versions, but delivery has been delayed while the aircraft maker has lost billions of dollars on the project.

The US President had earlier expressed frustration over Boeing's delays in delivering updated Air Force One aircraft and is exploring alternatives like buying an old one from another country.