Donald Trump has said he is sending treasury secretary Steven Mnuchin to China for talks as the two countries deal with tensions over trade and intellectual property.

Trump said during a White House news conference with President Emmanuel Macron of France that the US and China were “very serious” about trade issues and reiterated his plans to impose tariffs of up to $100bn more on Chinese goods.

“We’ve put on very substantial tariffs and that will continue unless we make a trade deal. I think we’ve got a very good chance of making a deal,” Trump said.

The US and China have moved to the brink of the most consequential trade dispute since the second world war. Both countries have proposed tariffs of $50bn on each other’s products; Trump is looking to impose tariffs up to $100bn more on Chinese goods.

Mnuchin has expressed optimism the countries could avoid a trade war. He met last week with financial officials from China, Japan and Europe.

In a sign of progress, Chinese President Xi Jinping vowed earlier this month to open China’s market wider to foreign companies, raising hopes the dispute with Washington could be resolved.

Beijing’s commerce ministry said last weekend that China would welcome a visit from the US to discuss trade issues.

US commerce secretary Wilbur Ross said China’s plan to transform itself into the global technology nexus is a “frightening” one that puts American intellectual property at risk.

“It’s a huge, huge problem,” Ross told a gathering of fabric industry executives about the theft of technology. “And it’s not going away.”

He said Beijing’s development plan – Made in China 2025 – maps out the country’s strategy to dominate “every hot industry” from space to telecommunications to robotics to electric cars.

“They have been the factory floor of the world, now their vision is to be the technology center for the world,” Ross said.

“What they are really trying to do is take their immense trade surplus from the conventional industries of today … and plow them into semiconductor research and every kind of research you can imagine.”

Guangzhou Automobile Group on Wednesday said a trade war could hurt its plans to break into the US market if tariff barriers were raised.

Feng Xingya, GAC Group president, told reporters at the Beijing auto show that increased US tariffs on imported Chinese vehicles would have a “significant” impact on its plans and strategy to break into the US by 2019.

“If the United States really levies a 25% tariff, it would have significant impact on us. We are now doing studies on our price competitiveness and profit potential [after any tariff increase],” Feng said at Asia’s largest auto show.