LONDON (AP) -- China accused Nvidia on Monday of violating the country's antimonopoly laws and said it would step up scrutiny of the world's leading chipmaker, escalating tensions with Washington as the two countries held trade talks this week.

Chinese regulators said a preliminary investigation found that Nvidia didn't comply with conditions imposed when it purchased Mellanox Technologies, a network and data transmission company.

The one-sentence statement from the State Administration for Market Regulation statement did not mention any punishment, but said it would carry out "further investigation."

An Nvidia spokesperson said, "We comply with the law in all respects. We will continue to cooperate with all relevant government agencies as they evaluate the impact of export controls on competition in the commercial markets."

Regulators said in December that they were investigating the company for suspected violations stemming from the $6.9 billion acquisition of Mellanox. The deal was completed in 2020 after the Chinese regulator gave conditional approval for Nvidia to buy the Israeli company.

The announcement, which came as the two sides held trade talks in Spain, is the latest tit-for-tat move between Washington and Beijing in their trade battle over technology focusing on semiconductors and the equipment to make them.

On Saturday, China's Ministry of Commerce said it was carrying out an antidumping investigation into certain analog IC chips imported from the U.S., including commodity chips commonly made by companies such as Texas Instruments and ON Semiconductor.

The ministry also announced a separate antidiscrimination probe into U.S. measures against China's chip sector.

A day earlier, the U.S. had sanctioned two Chinese companies accused of acquiring equipment for major Chinese chipmaker SMIC.

The talks in Madrid between U.S. Treasury Secretary Scott Bessent and Chinese Vice Premier He Lifeng in Madrid concluded Monday with Bessent telling reporters the two sides reached a framework deal for U.S. ownership of TikTok. However, details were scant and Chinese negotiators provided no confirmation of a deal.

It's the fourth round of discussions after meetings in London, Geneva and Stockholm. The two governments have agreed to several 90-day pauses on a series of increasing reciprocal tariffs, staving off an all-out trade war.

Santa Clara, Calif.-based Nvidia has become central to the U.S.-China trade war, as the two sides battle for tech supremacy. The artificial intelligence boom has fueled demand for the Nvidia's advanced processors, making it the world's most valuable company.

The company has faced restrictions on chip exports to China imposed by President Joe Biden's administration that were then reinforced by President Donald Trump. Nvidia won approval in July from the Trump administration to sell China its H20 graphics processing unit, which is less powerful and designed to comply with U.S. export curbs.

Nvidia violated antimonopoly laws, China says