China National Petroleum Corp. (CNPC), the country's biggest oil company, is set to become its first to seek an international stock market listing. The IPO, due soon, will total $7 billion, the biggest by a mainland Chinese company and topping China Telecom Hong Kong's $4.2 billion IPO in 1997. CNPC is awaiting approval to list on the New York Stock Exchange. The offering is likely to be controversial because U.S. civic and religious leaders have called on President Clinton to bar the company from U.S. capital markets. Their opposition is founded on CNPC's ties to Sudan, the target since 1997 of U.S. sanctions for alleged state-sponsored terrorism and human rights abuses. More than 20 Chinese state companies plan to list shares abroad this year.