China says it plans to file a fresh complaint against President Donald Trump’s tariffs at the World Trade Organisation (WTO).
The threat comes after the US imposed a second round of tariffs on $16bn (£12.4bn) of Chinese goods, in an escalation of their trade war.
The 25% tax came into effect at noon in Beijing (04:00 GMT), affecting goods including motorcycles and antennas.
There are fears that more tariffs could further hurt companies and consumers.
China’s commerce ministry warned of a “counter-attack” after Washington imposed the new tariffs, saying it “clearly suspected” the US of violating WTO rules. It filed the first complaint at the WTO in July.
On Thursday, China imposed retaliatory taxes on $16bn of US goods at the exact same time as the US levies came into force. The levies cover goods including coal, medical instruments, cars and buses.
A total of $50bn worth of imports from both sides will now be taxed under this second round.
The tit-for-tat tariffs come as officials from the US and China are holding low-level talks in Washington.
But hopes are not high they will bring a breakthrough in the trade row which began in July.
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Washington’s second round of tariffs has come despite testimony to the US Trade Representative’s Office by dozens of American companies and industry groups.
President Trump has taken an aggressive stance on trade with China
Many said the new tax would hurt their businesses and warned that they would not be able to absorb another tax without raising prices for US consumers.
However, the $16bn is a drop in the ocean compared to the amount Donald Trump has flagged could be hit.
The president said in July he was ready to tax all of the $500bn worth of Chinese imports into the US.
Grim outlook for the region
Karishma Vaswani, Asia Business correspondent
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What hurts Beijing can also hurt countries further afield.
Many goods that are needed for final assembly in China actually come from other South East Asian countries such as Malaysia and Indonesia, and go through Singapore to have some other products added on.
Economists say that means some countries in the Asia Pacific region could see as much as a percentage point shaved off economic growth.
International trade is what has helped Asia turn itself from an economic backwater into one of the most dynamic and fast growing areas in the world. It’s lifted millions out of poverty.
But if this trade war continues – the outlook could be far more grim.
The US has threatened a third round of tariffs on an additional $200bn of Chinese goods and they could come as soon as next month.
It has since said those products could be hit with a 25% levy – more than double the 10% originally planned.
China has said it would respond with another tariff on $60bn of US goods.
But it would be harder for Beijing to match the US threat because its manufacturers export far more products than American businesses send to China.
The US Trade Representative’s Office is holding hearings this week on the likely impact of more tariffs.
China has previously accused the US of “unilaterally” heightening tensions between the two economic giants.
There are signs the trade war is already having an impact.
Major carmakers recently warned that changes to trade policies were hurting performance.
The International Monetary Fund said last month an escalation of the tit-for-tat tariffs could shave 0.5% off global growth by 2020.