WASHINGTON, United States (AFP) — United States (US) President Donald Trump vowed to embrace trade wars Monday, promising tariffs and taxes on other countries in a nationalistic inaugural address after being sworn in as the 47th president.

“I will immediately begin the overhaul of our trade system to protect American workers and families,” he said at the US Capitol.

“Instead of taxing our citizens to enrich other countries, we will tariff and tax foreign countries to enrich our citizens,” Trump added.

Since his election victory in November, Trump has taken aim at allies and adversaries alike, raising the prospect of fresh tariffs to push other countries towards tougher action on US concerns.

Before his White House return, Trump vowed to impose 25 per cent tariffs on Canadian and Mexican imports, and an additional 10 per cent on Chinese goods, if they did not do more about illegal immigration and the flow of fentanyl into the United States.

On the campaign trail, Trump also floated the idea of much steeper tariff rates on Chinese imports.

But Trump stopped short Monday of unveiling new tariffs, which are applied on imported goods when a US buyer purchases them from abroad.

In his speech, he reiterated his plan to set up an “External Revenue Service” to collect tariffs, duties and revenues, alongside the establishment of a “Department of Government Efficiency” aiming to cut federal spending.