US president Donald Trump will announce on Friday plans to slam China with over US$50 billion per year of tariffs and other penalties.
The move is aimed at curbing theft of US technology and trade secrets, which Mr Trump has blamed for hurting the US economy and workers.
However the aggressive measures are likely to trigger retaliation from Beijing and stoke fears of a global trade war.
There was no indication of the size and the scope of tariffs, which US trade representative Robert Lighthizer said on Wednesday (local time) would target China's high technology sector and which could also include restrictions on Chinese investments in the United States. Other sectors like apparel could also be hit.
"Tomorrow the president will announce the actions he has decided to take based on USTR's 301 investigation into China's state-led, market-distorting efforts to force, pressure, and steal US technologies and intellectual property," the official said.
Mr Lighthizer told the House of Representatives Ways and Means Committee, a top economic body, that the aim would be to minimize the impact of any tariffs on US consumers.
China has threatened to retaliate by hitting US agricultural exports if tariffs on Chinese imports are announced by Washington.
The United States runs a hefty trade deficit with China of US$375 billion, caused largely by its savings deficit and rising budget deficit.
Estimates of the cost of counterfeit goods, pirated software, and theft of trade secrets and could be as high as US$600 billion, according to one influential study.