Embarking on his first full week in office, the 45th US president began rolling out his policy agenda after a tumultuous first weekend for his administration by signing a series of executive orders.
Among the first was a memo on withdrawing from the vast TPP trade pact, which aimed to set trade rules for the 21st century and bind US allies against growing Chinese economic clout.
"We've been talking about this for a long time," Trump said as he signed the executive order in the Oval Office.
"Great thing for the American worker what we just did."
Promoted by Washington and signed by 12 countries in 2015, the TPP had yet to go into effect and US withdrawal is likely to sound its death knell.
Its signatories - Australia, Brunei, Canada, Chile, Japan, Malaysia, Mexico, New Zealand, Peru, Singapore, the United States and Brunei - together represent 40 per cent of the world economy.
The real estate mogul's White House bid was fuelled in part by a pledge to overturn trade deals - such as TPP and the North American Free Trade Agreement - that he says have drained US jobs and destroyed its industrial heartlands.
Trump also signed two other orders, on freezing the hiring of federal workers and hitting foreign NGOs that help with abortion.
