China is urging solar companies to fight against trade policies from countries such as the U.S. and India that are creating challenges for the industry.

Companies should use legal weapons to fight trade restrictions against solar products, while the industry should enhance its autonomy, resilience and credibility, Wang Xin, deputy chief of the Trade Remedy and Investigation Bureau at the Commerce Department, said in a virtual presentation at a solar industry conference Wednesday.

“Trade frictions are still at a high prevalence globally, and photovoltaic products are among the hardest-hit areas,” Wang said. “This is building up trade protection systems and increasing trade frictions, which have brought severe challenges to our solar companies.”

The Commerce Department bureau will continue to protect and assist companies when they expand in international markets, Wang said.

Shares of Chinese solar companies erased earlier gains Wednesday after the U.S. House passed legislation that would ban goods coming from the Xinjiang region unless companies can prove they have not been made with forced labor. U.S. Customs has detained solar panel imports from several Chinese companies on suspicions they contain silicon material from a company with ties to Xinjiang that was hit with sanctions in June.

A U.S. trade agency has also recently recommended extending Trump-era tariffs on solar components. India earlier this year announced a 40% levy on imports of solar modules to cut dependence on foreign supplies and boost domestic manufacturing of the equipment.