BEIJING announced today that it has lodged a challenge to a US tariff increase on solar panels with the World Trade Organisation.

The 30 per cent tariffs unveiled in January improperly help US producers in violation of WTO rules, the Commerce Ministry said, revealing that a formal complaint had been filed on Tuesday with the WTO in Geneva.

Washington’s action “seriously damaged China’s trade interests” and “also affects the seriousness and authority of WTO rules,” the ministry said.

The solar panel duties are separate from higher tariffs imposed by the Trump administration that came into effect in July on Chinese imports in response to allegations that China steals or presses companies to hand over technology.

They also apply to imports of solar cells and modules from Europe, Canada, Mexico and South Korea, straining relations with Washington’s allies.

US President Trump has defended the solar tariffs as necessary to protect US producers, claiming that import prices are unfairly low due to subsidies and other improper support.

Washington took action under a 1974 domestic law instead of going through the WTO, sparking complaints it was undermining the global trade body.

WTO complaints begin with negotiations between parties to the dispute. If those fail, the case moves to a panel of experts who can decide whether the trade controls are improper.

In their technology dispute, Washington imposed 25 per cent duties on $34 billion (£27bn) of Chinese goods it said benefit from improper industrial policies.

Beijing responded with similar penalties and further tit-for-tat measures are in the pipeline.