WASHINGTON (Reuters) - The Obama administration is expected to launch a complaint against Chinese aluminum subsidies with the World Trade Organization on Thursday, a person familiar with the matter said.

The complaint will likely add to rising trade tensions between the world's two largest economies as President-elect Donald Trump prepares to take office next week with pledges to reduce U.S. trade deficits with China as a top priority.

The complaint, to be filed by the U.S. Trade Representative's office, is expected to cite "artificially cheap loans" from Chinese banks and low-priced inputs for Chinese aluminum makers as contributing to excess capacity and hurting American workers and companies.

(Reporting by David Lawder; Editing by Leslie Adler)