US President-elect Donald Trump has unveiled plans to slap a 25 percent tariff on all products coming into the US from Canada and Mexico. He also pledged a 10 percent levy on Chinese goods.

On social media, Trump said he will impose the charges as one of his first acts in office.

He claims both Canada and Mexico have allowed drugs and "illegal aliens" to flow across their borders.

He says both countries have the power to stop it, and until they do, they will "pay a very big price."

Trump also said China is allowing drugs, especially fentanyl, to enter the US. He says the 10 percent tariff on all Chinese goods will stay in place until the drugs stop coming.

Trump says that's in addition to any other tariffs he places on China's imports.