China has hit back against sweeping US export controls on chips, filing a dispute with the World Trade Organization and escalating the tech war between the two countries.

China’s commerce ministry said on Monday its WTO complaint was a legal and necessary measure to defend its “legitimate rights and interests,” after the US Department of Commerce introduced sanctions in early October to make it harder for China to buy or develop advanced semiconductors.

“At a minimum, the case is about China pushing back on how it’s perceived as an unfair actor in the global trading world,” said Ben Kostrzewa, an expert on US-China trade relations at Hogan Lovells.