WASHINGTON (AP) _ An effort by China to raise $5 billion by offering stock in its national oil company comes amid high oil prices and strong investor interest in new offerings _ and strong opposition from the American labor movement.

Warning that investment in the PetroChina initial public offering (IPO) carries high risk and could bolster an abusive regime, the AFL-CIO is launching its first assault against a planned international stock offer.

AFL-CIO President John J. Sweeney called more than two dozen key financial analysts Thursday to warn of risks with the Chinese stock and express concern over labor problems and human rights abuses in China, the labor federation said.

A top investment bank, Goldman Sachs & Co., is beginning an international effort next week to spur interest in the PetroChina IPO. Share prices have not yet been set, and Goldman, the lead underwriter of the offering, declined to comment on the stock, citing the Wall Street tradition of a ``quiet period'' around the time of a new equity offer.

``We think this deal is impossible to reform,'' said Bill Patterson, AFL-CIO investment director. ``There is no way this transaction, with the relationship to the Chinese state, can be structured in a way to protect investors.''

He said that with billions in union members' savings and pension funds invested abroad, U.S. workers are becoming key investors in world markets. The action against PetroChina is the first of many efforts to ensure that those investments are not in entities that abuse laborers, he said.

The public stock offering, intended for listing on the New York Stock Exchange and other markets, would make available a 15 percent share in PetroChina Co. Ltd. to fund its capital spending and investments and reduce borrowing, according to its Feb. 29 filing. The company was formed by China National Oil Co., and 85 percent interest in PetroChina will be retained by the Chinese government.

Little information is readily available about planned operation of PetroChina, however, since as a foreign entity, it was not required to file its offering electronically. It is the Chinese government's producer of crude oil and natural gas.

The stock offering has some attraction because it comes at a time of high global oil prices and amid strong support from the Clinton administration for granting China permanent normal trade status and membership in the World Trade Organization.

The AFL-CIO also opposes those steps, and China has strong opponents on Capitol Hill.

The congressionally-mandated U.S. Commission on International Religious Freedom last month appointed a task force to monitor its plans to raise money on U.S. stock markets. The commission objects to the Chinese oil company's projects in Sudan, which is under U.S. sanctions for human rights abuses.