Washington, Aug. 14 -- US President Donald Trump has threatened to pull Washington out of the World Trade Organization (WTO) following "years of mistreatment" at the hands of the organization.

Speaking at a campaign rally in Pittsburgh, Pennsylvania, on Tuesday, Trump said: "We will leave if we have to."

"They have been s****ing us for years, and it's not going to happen any longer," he said, according to media reports.

The WTO is an intergovernmental organisation that regulates international trade between nations.

Trump said the US does not need the WTO if it fails to address loopholes that favour certain nations. He has repeatedly criticized the organization, claiming that Washington is disadvantaged as a member of the global bloc....