US President Donald Trump said he is not aware of a ruling by the World Trade Organization in a trade dispute with China;

But he will look into it.

On Tuesday, Trump reaffirmed that he was not a fan of the WTO, which said today that the United States violated global rules by imposing billions of dollars in fees in the midst of Trump's trade war against China.

When asked about the decision upon leaving the White House, Trump said, "So we will have to do something about the WTO because they allowed China to get away with its crime."

He added, "We will look at it, but I am not a fan of the trade organization .. I can say this from now, so perhaps they would do us a great favor."

On Tuesday, the World Trade Organization ruled that the additional fees imposed by the United States on China in 2018 were not justified in global trade rules.

A three-member panel ruled that Washington had not provided evidence that the fees it imposed after an investigation were an exception that justified its obligations.

Washington imposed duties on Chinese exports worth more than 550 billion dollars, and Beijing made response decisions.

Beijing had submitted the file to the World Trade Organization in 2018, and it related to a first package of tariffs imposed by Washington on Chinese goods worth 250 billion dollars.

These punitive fees marked the beginning of the trade war between the two economic giants, and formed one of the major decisions during Trump's presidency.

America imposed customs duties on China for half a trillion dollars before the truce agreement was signed last January (Getty Images)

No effect

For his part, US Trade Representative Robert Leitzer said, Tuesday, that the World Trade Organization ruling against US duties on Chinese products shows that the world organization is "completely insufficient" to prevent unfair trade practices.

"The United States should be allowed to defend itself against unfair trade practices," he added.

"It is important to note that this report (issued by the World Trade Organization) has no effect on the historic first phase trade agreement between the United States and China," the US official said.

Robert Leitzer is the architect of the bilateral trade agreement with Beijing signed last January, which allowed for a truce in the trade dispute, which strongly affected the two largest economic powers in the world.

And Washington can veto the decision effectively by filing an appeal at any time within 60 days.

The Trump administration has already set up the World Trade Organization's appeals body, a tactic that has rendered the world's first trade ruling ineffective.

The dispute centers around the Trump administration's use of a US trade law dating back to the 1970s.

To launch its unilateral trade war against China in 2018.

China says the tariffs violated the WTO's most favorable country treatment clause;

Because the measures did not provide the same treatment for all WTO members.

China maintains that the fees violate a major dispute settlement rule that requires countries to first seek recourse to the World Trade Organization before imposing retaliatory measures against another country.