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 (06:00 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.