WASHINGTON (Reuters) - Wilbur Ross, President-elect Donald Trump’s nominee for Commerce Secretary, has pledged to sell his stake in his main private equity firm and resign from corporate boards but will keep his interests in mortgage lending and shipping. In an ethics agreement published on Tuesday, the billionaire investor vowed to sell shares in Invesco Ltd (IVZ.N), the parent company of W.L. Ross & Co, valued at up to $50 million. He also pledged to divest other assets worth between $77 million and $209 million to prevent conflicts of interest. He is due to be questioned by members of the Senate Commerce, Science and Transportation Committee on Wednesday at a confirmation hearing. The federal disclosure forms for presidential appointees allow asset values to be listed in wide ranges with a maximum threshold of “over $50 million”. Picked by Trump to lead an agenda aimed at shrinking U.S. trade deficits with China and Mexico, the 79-year-old Ross is estimated by Forbes to be worth about $2.5 billion. His asset sales would represent a small portion of that total. Ross earned his fortune in part by running businesses that have offshored thousands of U.S. jobs, according to Labor Department data seen by Reuters.  He once served under former U.S. President Bill Clinton on the board of a fund set up by the U.S. government to make private investments in Russia, and worked as a privatization advisor to former New York City Mayor Rudy Giuliani. Ross said he would divest financial interests in some 80 entities, including ownership stakes in companies and investment partnerships, stocks and bonds. He said he would retain his holdings in nine entities related to his mortgage finance and trans-oceanic shipping assets, but will resign positions he has in those companies and partnerships. The disclosure form lists the valuations of those interests at about $8 million to $36 million. He will also resign from positions at 22 of the business entities from which he is divesting, including giving up his board seats at steelmaker ArcelorMittal ISPA.AS and Bank of Cyprus BOC.CY, and at chemicals and plastics distributor Nexeo Solutions (NXEO.O) where he is chairman of the board. His stake in Nexeo is the largest single investment that he plans to sell, valued in the 57-page financial disclosure at $25 million to $50 million. His steel industry investments may have brought Ross the most unfavorable media coverage. He listed his shares in ArcelorMittal, which bought his International Steel Group in 2004, as being worth $750,000 to $1.5 million.   Other assets that Ross intends to keep include two cash accounts holding more than $50 million each, the largest reporting threshold required on the forms, and an art collection valued at more than $50 million.  