President-elect Donald Trump threatened to return the Panama Canal to U.S. control, and accused the country of charging "ridiculous" fees for passage through the waterway.

In a December 21 post to his Truth Social platform, Trump said that the canal is a "vital national asset" for the U.S., and that he will not let it fall into the "wrong hands." He went on to assert that the waterway was not given to Panama to charge U.S. businesses "exorbitant" fees, and that the U.S. has been "treated in a very unfair and injudicious way" by the authority that governs the canal.

"This complete 'rip-off' of our Country will immediately stop," he added.

A day later, Panama President José Raúl Mulino — a populist conservative who has largely aligned with Trump's policies in the past — posted a video to social media stating that "every square meter of the Panama Canal and its adjacent zones is part of Panama, and it will continue to be." Trump responded shortly after, saying simply, "we'll see about that!" 

The Panama Canal opened in 1914, and was operated by the U.S. for much of the 20th century, until then-President Jimmy Carter signed a pair of treaties with Panama's leader Omar Torrijos in 1977 to phase out U.S. control. The two countries jointly operated the waterway for the next 22 years, before Panama assumed full control in 1999. With transits having fallen in recent years, the canal authority is planning to increase fees in 2025 by $1,000-$3,000 per vessel depending on size and cargo.