It also appealed a ruling that it was flouting international trade rules by labelling imports from Hong Kong as being from China.

Former US president Donald Trump’s administration introduced the tariffs on steel and aluminium imports from China, Norway, Switzerland and Turkey.

Marking a departure from a decades-long US-led drive for free trade, Trump justified the steep tariffs with claims that massive flows of imports to the United States threatened national security.

The administration of his successor, President Joe Biden, has taken a less combative tone but has stuck with the tariffs.

The expert panels the WTO set up in 2018 to settle complaints filed over the tariffs ruled last month that they were inconsistent with various articles of the General Agreement on Tariffs and Trade (GATT).

The panels also determined that these inconsistencies were not justified by the security exceptions provided for in the GATT, as they were not applied in a time of war or during a case of serious international tension.

“Fundamentally flawed”

US Ambassador Maria Pagan criticised the rulings during a meeting of the WTO’s Dispute Settlement Body (DSB) on Friday.

“The United States will not cede decision-making over its essential security to WTO panels,” she said.

“For over 70 years, the United States has held the clear and unequivocal position that issues of national security cannot be reviewed in WTO dispute settlement,” she said.

“The United States cannot support adoption of these fundamentally flawed and damaging reports,” she said, announcing the US decision to appeal.

Washington has also appealed a separate ruling issued last month faulting it for another decision under Trump to stop stamping products as “Made in Hong Kong”, and instead labelling them as Chinese-made.

After Hong Kong filed a complaint arguing that the move ignored its status as a separate WTO member, a DSB panel ruled the US shift in origins markings was “not justified” under global trade rules.

The WTO Appellate Body

In the past, the WTO Appellate Body would have had three months to rule on any appeals filed.

But the appeals tribunal — also known as the supreme court of world trade — has been frozen since late 2019, after the United States under Trump blocked the appointment of new judges and demanded a dramatic overhaul.

By filing appeals into a void, Washington has in effect blocked China’s ability to move forward and request financial compensation for the US activities deemed illegal by the DSB.

The issue of US tariffs on Spanish olives also came up during Friday’s meeting.

In late 2021, a WTO panel ruled the steep import duties slapped on Spain’s iconic agricultural export by the Trump administration in 2018 violated international trade laws and demanded that Washington rectify the situation.

The United States said Friday it had done so, but the European Union disagreed and said it was considering the next steps to make sure the WTO ruling is respected.