US President Donald Trump has threatened to withdraw the United States from the World Trade Organization (WTO), a move that would throw global trade into wild disarray.

In an interview with Bloomberg News on Thursday, Trump said, “If they don’t shape up, I would withdraw from the WTO,” in his latest criticism of the institution.

Trump, who is a fierce critic of the WTO, has already reportedly talked with his advisers about the issue.

He has complained frequently that the United States is treated unfairly in global trade and has sharply criticized the WTO for letting that happen.

Trump said last month that the United States is at a big disadvantage from being treated “very badly” by the WTO for many years and that the organization needs to “change their ways.”

The US president has threatened to take action against the global body, although he has not specified what form that could take.

Trump would need congressional approval to pull the US out of the Geneva-based body, which is unlikely.

The move would undercut the legitimacy of the WTO, remove the largest economy from it, and trigger the possibility that countries would stop following the system of trade rules created by the international community.

This comes as US tariffs on still and aluminum imports have drawn sharp criticism from around the world with several countries, in return, taking retaliatory measures.

Trump announced steel and aluminum tariffs in March as a way to alleviate what he described as unfair trading practices.

He believes the tariffs will safeguard US jobs even but economists say the measures will destroy more jobs than they create and will hurt the very US companies and workers that Trump has said he aims to protect.

Trump also pulled out of negotiations for the Trans-Pacific Partnership shortly after taking office last year and began renegotiating the North American Free Trade Agreement with neighbors Canada and Mexico.