(Reuters) -U.S. President-elect Donald Trump said on Monday that on his first day in office he would impose a 25% tariff on all products from Mexico and Canada, and an additional 10% tariff on goods from China, citing concerns over illegal immigration and the trade of illicit drugs.

"On January 20th, as one of my many first Executive Orders, I will sign all necessary documents to charge Mexico and Canada a 25% Tariff on ALL products coming into the United States, and its ridiculous Open Borders," Trump said in a post on Truth Social.

Trump said the tariffs would remain in place until the two countries clamp down on drugs, particularly fentanyl, and migrants crossing the border illegally.

On China, the president-elect accused Beijing of not taking strong enough action to stop the flow illicit drugs crossing the border into the U.S. from Mexico.

"Until such time as they stop, we will be charging China an additional 10% Tariff, above any additional Tariffs, on all of their many products coming into the United States of America," Trump said.

Trump has previously pledged to end China's most-favored-nation trading status and slap tariffs on Chinese imports in excess of 60% - much higher than those imposed during his first term