President Donald Trump has threatened to withdraw the US from the World Trade Organisation (WTO) if the body fails to change the way it treats America.
"If they don't shape up, I would withdraw from the WTO," the BBC quoted Trump as saying in an interview with Bloomberg News on Friday.
The WTO was established to provide rules for global trade and resolve disputes between countries. However, Trump, who has been pushing protectionist policies, says the US is treated unfairly by the body, the BBC reported.
His warning about a possible US pull-out from the organisation highlights the conflict between the president's trade policies and the open trade system that the WTO oversees.
Washington has also blocked the election of new judges to the WTO's dispute settlement system, to potentially paralyse its ability to issue judgments.
Trump has been sounding off about unfair trade since even before he became president. In 2017, Trump told Fox News: "The WTO was set up to benefit everybody but us… We lose the lawsuits, almost all of the lawsuits in the WTO."
The US has been embroiled in a tit-for-tat trade battle on several fronts in recent months. The one creating the most interest is the one with China, as the world's two largest economies wrangle for global influence.
Trump has introduced tariffs on a number of goods imported into the US.
A third round of tariffs on $200 billion of Chinese goods could come as soon as a public-comment period concludes next week, the BBC quoted a report as saying.
Asked to confirm this during his interview, Trump said that it was "not totally wrong", the BBC quoted him as saying.
China's commerce ministry has said it "clearly suspects" the US of violating WTO rules.
An initial complaint at the WTO was filed by China in July after Trump imposed his first round of tariffs.
The WTO, which was set up in 1994, is at the heart of the system of rules for international trade. It is the forum for sorting disputes between countries about breaches of global trade rules and it is the forum for negotiating new trade liberalisation.