Washington DC/IBNS: US President Donald Trump Saturday ordered 25 percent tariffs on Canadian and Mexican imports and 10 percent on goods from China, citing a "major threat" by "illegal aliens".

The move has triggered strong retaliation from Ottawa and Mexico City.

Donald Trump signed three separate executive orders on the tariffs which have the potential to trigger a new trade war.

"We need to protect Americans, and it is my duty as President to ensure the safety of all. I made a promise on my campaign to stop the flood of illegal aliens and drugs from pouring across our borders, and Americans overwhelmingly voted in favor of it," he posted on social media.

While Canadian and Mexican exports to the US will face a 25 percent tariff, the White House said energy resources from Ottawa will have a lower 10 percent levy "until the crisis is alleviated".

"The Biden Administration's policies have fueled the worst border crisis in U.S. history. More than 10 million illegal aliens attempted to enter the United States under Biden's leadership, including a rising number of Chinese nationals and people on the terror watch list," the White House said in a statement.

Responding to Trump's tariffs, Canadian Prime Minister Justin Trudeau said they "did not want this, but Canada is prepared".

He later announced 25 percent retaliatory tariffs.

Mexican President Claudia Sheinbaum Pardo also hit back, saying "The problems are not resolved by imposing tariffs, but by talking and dialoguing".

"I instruct the Secretary of Economy to implement Plan B that we have been working on, which includes tariff and non-tariff measures in defense of Mexico's interests," she posted on X.

There was no immediate reaction from China.