China is filing a complaint with the World Trade Organisation against US tariffs on steel and aluminium products.
The Geneva-based trade body said China has requested 60 days of consultations with the US to resolve the dispute.
If the two sides cannot agree on a solution, the next step could be for Beijing to request a ruling from a panel of trade experts.
China claims the duties of 25% on imports of steel and 10% on imports of aluminium products breach international trade rules.
Earlier, president Xi Jinping promised to cut China's vehicle import tariffs and improve intellectual property protection in possible concessions aimed at defusing a worsening trade dispute with Washington.
Speaking at a business conference, Mr Xi made no direct mention of his American counterpart, Donald Trump, or the dispute.
He promised progress on areas that are US priorities including opening China's banking industry and boosting imports but did not address key irritants for Washington such as a requirement for foreign companies to work through joint ventures that require them to give technology to potential local competitors.
Mr Xi tried to position China as a defender of free trade and cooperation, despite its status as the most-closed major economy, in response to Mr Trump's "America first" calls for import restrictions and trade deals that are more favourable to the United States.
"China's door of opening up will not be closed and will only open wider," Mr Xi said at the Boao Forum for Asia on the southern island of Hainan.
Mr Xi said Beijing will "significantly lower" tariffs on vehicle imports this year and ease restrictions on foreign ownership in the car industry "as soon as possible".
Private sector analysts saw Mr Xi's speech as an overture to help end the biggest global trade dispute since the Second World War. It has fuelled fears the global economic recovery might be set back if other governments are prompted to raise their own import barriers.
Mr Trump has threatened to raise tariffs on Chinese goods worth $50bn in response to complaints that Beijing pressures foreign companies to hand over technology in violation of its WTO market-opening commitments. Beijing fired back with its own $50bn list of US goods for possible retaliation.
BREAKING OVERNIGHT: President Trump has announced the possibility of $100 billion more in tariffs on Chinese goods in addition to the $50 billion already announced. The Chinese Commerce Ministry said today it “will not hesitate to fight back at any cost.” pic.twitter.com/go0fBBoKPu— ABC World News Now (@abcWNN) April 6, 2018
The Chinese leader promised to encourage "normal technological exchange" and to "protect the lawful ownership rights of foreign enterprises".
Such pledges might help, Rajiv Biswas of IHS Markit said in a report.
"President Xi's speech could create a very good platform to launch US-China dialogue at the WTO to find a deal on intellectual property rights that will address US concerns," Mr Biswas said.
"This would be a victory for the world trading system and an important step away from the abyss of rising global protectionism."
- Digital Desk and Press Association