China’s market regulator has said US computer chipmaker Nvidia has violated Chinese anti-monopoly laws.

The country’s market watchdog did not give details of how Nvidia had breached the rules, but said it would continue to investigate the matter.

It comes as US and Chinese officials are holding a second day of trade talks in Spain on Monday in the latest attempt to end a trade war between the world’s two biggest economies.

The negotiations, led by US Treasury Secretary Scott Bessent and Chinese Vice Premier He Lifeng, also come as the deadline looms for the Chinese owner of TikTok to find a buyer or face a ban in America.

Top level trade delegations from Beijing and Washington last met in July, when they struck a deal to extend their tariffs truce by another 90 days until 10 November.

During this week’s talks, officials are also expected to lay the groundwork for a potential meeting between Trump and Chinese President Xi Jinping as soon as October, when they are scheduled to attend a summit in South Korea.

The tariffs truce between China and the US cut import taxes that had reached more than 100% on each other’s goods.

The extension gave them more time for negotiations about “unfair trade practices” and to address national security issues, the White House said.

China launched an investigation into Nvidia in December last year which was seen as the latest retaliation in a battle between the US and China over the semiconductor chip market.

The US had been tightening restrictions on sales of certain exports to Chinese companies, including high-end semiconductors.

The talks in Madrid are expected to address the issue of what chips, including those made by Nvidia, are allowed to enter China.

After initially calling for TikTok to be banned during his first term, Trump has reversed his stance on the popular video-sharing app and delayed the ban three times so far.

The BBC has contacted Nvidia, the White House and TikTok for comment.

Speaking to reporters on Sunday, Trump said: “We may let [TikTok] die. Or we may… I don’t know. It depends. Up to China, it doesn’t matter too much.”

It came as expectations grow that the deadline, which is due to expire on Wednesday, will be extended for a fourth time.

Last month, Trump suggested that he would keep extending the deadline until a buyer for TikTok could be found and called national security and privacy concerns related to the app and its Chinese parent company ByteDance “highly overrated”.

Trump was highly critical of TikTok during his first term in the White House but softened his position after he gained popularity on the app during the 2024 presidential election.

In August, The White House launched its official TikTok account.

The app is one of the world’s most widely-used social media platforms, with around 170 million users in the US.