President Donald Trump says 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.

Among the ways being discussed to force faster delivery of two presidential planes are relaxing security clearances for Boeing workers and even purchasing a temporary luxury plane and retrofitting it.

U.S. President Donald Trump said on Wednesday he was not happy with planemaker Boeing and his administration might have to go a different route with Air Force One planes.