The World Trade Organization has said some US tariffs on Chinese goods do not comply with its rules, opening the door for Beijing to levy retaliatory sanctions.

The ruling from the WTO appellate body late on Tuesday on the case, which predates the current trade war between the two countries, was blasted by the US trade representative office, which claimed the report was undermining its own rules. 

The findings deliver a blow to Washington’s attempts to push back against what it views as unfair state-led pricing for some types of goods, such as piping and solar panel components, and comes at a time when the US and China are already locked in a bitter trade dispute that has seen hundreds of billions of dollars in tariffs imposed on exports on both sides of the Pacific.