The tariffs on steel and aluminum imports proposed on March 1 and signed into law by U.S. President Donald Trump on March 8 have sparked concerns of a global trade war and frayed investors' nerves.

Trump will likely announce tariffs on Chinese imports by Friday, a source in the administration said, as the top U.S. trade diplomat told lawmakers he had the tools to strike back over Chinese theft of U.S. technology know-how.

A report in the Wall Street Journal said China was planning counter-measures against U.S. tariffs.

Among the most affected could be the technology sector, particularly semiconductor companies, which have high revenue exposure to China, according to UBS.

Shares of U.S. exporters of agricultural products such as soybeans and meat slipped on Wednesday. The Journal report said China was preparing tariffs targeted at U.S. agriculture exports.

Other business areas with companies that have high revenue exposure include the life-science tool industry and the consumer discretionary sector.

(Reporting by Lewis Krauskopf, April Joyner and Caroline Valetkevitch; Editing by Peter Cooney)

Stocks treated in this article : Microchip Technology, Xilinx, Amphenol, Qorvo