Donald Trump has withdrawn the USA from the TTP agreement
In an Oval Office ceremony, Mr Trump called the order a "great thing for the American worker."
The move will now raise fears in Brussels the TTIP deal, promoting cross-Atlantic trade with the EU, could also be under threat.
The TPP agreement was a huge part of former president Barack Obama’s eight-year term, with the long-negotiated deal covering 40 per cent of the world economy.
The deal, which Mr Trump previously criticised as a “potential disaster for our country”, was signed by 12 countries, including Japan, Australia, New Zealand and Mexico.
It aimed to reduce tariffs for cross-country trade and was considered an economic miracle due to the vastly differing countries involved.
The USA's withdrawal will be a massive blow to those involved and to the future of international trade.
The best photos from Donald Trump's historic inauguration
Mon, January 23, 2017
The inauguration of Donald Trump as the 45th President of the United States will mark the commencement of the four-year term of Donald Trump as President and Mike Pence as Vice President. A public ceremony will be held on Friday, January 20, 2017.
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President Donald Trump waves as he walks with first lady Melania Trump and son Barron during the inauguration parade.
Mr Trump said this afternoon: "Great thing for the American worker what we just did."
He had announced an "America first" presidency during his inauguration speech and this marks his first effort to deliver on that promise.
Mr Trump said withdrawing from the TPP agreement was a "great thing for the American worker"
The new President also signed an order today imposing a federal hiring freeze and a directive banning US non-governmental organisations receive federal funding from providing abortions abroad.
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