Two large American oil companies that received profitable vouchers to buy Iraqi oil under the United Nations' oil-for-food program said yesterday that the purchases complied with U.S. law.

Exxon Mobil Corp. and ChevronTexaco Corp. said that companies they controlled before a series of mergers -- Mobil Export Corp., Chevron and Texaco -- all acted properly when they participated in the program, spokesmen said.

The companies were required to obtain permission from the U.S. government and the United Nations to purchase Iraqi oil under the program. Exxon Mobil spokeswoman Prem Nair said Mobil Export followed that procedure for purchases in 1997 and 1998. A spokesman for ChevronTexaco, Stan Luckoski, said its predecessor companies bought oil "in full compliance with all applicable laws" but could not provide any additional detail.

Those companies, with three U.S. citizens, were among those named in a report released last week by U.S. weapons inspector Charles A. Duelfer, who concluded that Iraq did not possess stockpiles of illicit weapons immediately prior to the U.S.-led invasion. The lengthy report also examined the oil-for-food program, and included names of companies and individuals around the world that traded in Iraqi oil. In most instances, however, the names of the U.S. companies and citizens were expunged from the version of the report that was released publicly. Officials said they did so because of privacy laws.

The identities of the U.S. companies and the individuals were provided to The Washington Post by congressional sources. That information was reported Saturday by the New York Times and Los Angeles Times.

Between 1996 and 2003, U.S. companies and individuals joined those from other countries in receiving vouchers allowing them to obtain oil and to profit from selling or trading it. Together, U.S. companies and individuals received vouchers for more than 100 million barrels of oil.

The U.N. oil-for-food program -- under which vouchers were granted -- was created to allow Iraq to raise money for food, medicine and other critical, peaceful needs while the nation was under sanctions. But Duelfer's report said that former Iraqi president Saddam Hussein also used the program to extract cash kickbacks from some of those he did business with.

A federal grand jury in New York is investigating oil transactions under the program, according to several companies that have received subpoenas. Several congressional committees also are investigating the oil transactions, as is a U.N.-appointed panel.

A spokesman for the United Nations, Stephane Dujarric, said he could not comment on whether the U.S. companies followed requirements to obtain Iraqi oil. A spokeswoman for the Treasury Department, Molly Millerwise, said the Office of Foreign Assets Control is reviewing the licenses it issued as part of the oil-for-food program to determine whether laws were broken.

The report by Duelfer also named these individuals as having received vouchers: Oscar S. Wyatt Jr., a Texas oilman; Samir Vincent, a Fairfax County businessman; and Shakir Khafaji of the Detroit area. None returned phone calls.

In addition, the report named Bayoil and Coastal Corp., which has since become part of El Paso Corp. Bayoil officials did not return phone calls. El Paso Corp. recently filed documents with the Securities and Exchange Commission saying it had been subpoenaed by the grand jury investigating the oil transactions. A company spokeswoman said she could not provide additional comment.

The vouchers were potentially profitable. The report estimated profit margins of 15 cents a barrel to 85 cents a barrel.

Of the U.S. companies and citizens involved, the most oil was allocated to Wyatt and his company, Coastal. Combined, he and his company could have received estimated profits of more than $20 million, the report said.

Staff writer Colum Lynch at the United Nations contributed to this report.