US president Donald Trump has assumed office and outlined a new approach to international trade policy, with the renegotiation of the North American Free Trade Agreement (NAFTA) cited as a top priority.

Since taking up the presidency on January 20th, the Republican has pledged to speak to Canadian prime minister Justin Trudeau and Mexican president Enrique Pena Nieto - both of whom are scheduled to meet with Mr Trump soon - about the prospect of reforming the trade deal, which he has criticized sharply in the past.

Originally implemented by former president Bill Clinton, NAFTA created a trilateral trade bloc in North America consisting of the US, Canada and Mexico. During his presidential campaign, Mr Trump described the agreement as "the single worst trade deal ever approved" by the US, saying it has led to American jobs relocating to Mexico.

The new president has shown considerable opposition to a number of key US FTAs and has also confirmed that his government will seek to withdraw from the Trans-Pacific Partnership as part of a broader commitment to "rejecting and reworking failed trade deals".

A statement from the White House said: "President Trump is committed to renegotiating NAFTA. If our partners refuse a renegotiation that gives American workers a fair deal, then the president will give notice of the US's intent to withdraw from NAFTA."

Mr Trump is also set to meet with British prime minister Theresa May this week, with the prospect of a new free trade deal between the US and the UK expected to be high on the agenda.

Having shown strong support for the UK's decision to leave the European Union, the new president's team has been positive about the prospect of a bilateral US-UK agreement that would be introduced post-Brexit.