Presidential candidates Rudy Giuliani and John Edwards, who have spoken out about genocide in Darfur, did not know their financial holdings included investments in companies that do business in Sudan, aides said Thursday.

An Edwards campaign spokesman said the former Democratic senator from North Carolina would sell thousands of dollars of Sudan-related funds.

"He did not know about it and will divest," Eric Schultz said following inquiries about Edwards' portfolio.

Giuliani, the Republican former mayor of New York, has at least one investment of between $500,000 and $1 million in a fund that holds stock in a company that is active in Sudan.

"The mayor was unaware of this connection, but is taking it very seriously," spokeswoman Maria Comella said.

She said Giuliani and his staff would review his portfolio and "ultimately take appropriate action."

The Sudan-related investments illustrate the pitfalls for candidates with vast holdings that are scrutinized during a presidential campaign.

Edwards and his wife reported more than $29 million in assets in his financial disclosures this week. Giuliani and his wife listed assets of similar size.

Earlier, two other presidential candidates, Democratic Sen. Barack Obama of Illinois and Republican Sen. Sam Brownback of Kansas, said they had divested their holdings of Sudan-related stock.

Obama placed the total value of his divestitures at $180,000. The sales of the investments were recorded in their financial disclosures.

Last year Brownback was among members of Congress who wrote 44 governors to urge them to divest their employee pension funds from businesses linked to Sudan.

According to Giuliani's financial disclosure, he invested between $500,000 and $1 million in a Vanguard Wellington Fund. Data compiled by the Sudan Divestment Task Force shows that Vanguard Wellington has a small percentage of stock in Schlumberger Ltd. a French oil field services company that does business in Sudan.

Edwards sold stock he and his wife owned in Schlumberger for between $40,000 and $100,000. But his 401(k) and his children's trust invested between $30,000 and $100,000 in American Europacific Growth, which has stock in several companies that do business in Sudan.

He also invested $50,000 to $100,000 in Evergreen Equity Income Fund, another fund identified by the divestment task force as having stock in Sudan-related companies.

Both Edwards and Giuliani have called for the United States to do more to end the conflict that killed more than 200,000 people and displaced millions.

At a fundraiser in March, Giuliani said the Bush administration should hold an international summit on Sudan to "help stem the tide of genocide."

Edwards has said the United States and NATO allies should punish the Sudanese government and impose a a no-fly zone over the country's Darfur region. He also called for a U.N. peacekeeping force on the ground.

"This is a huge moral issue for America and the world," Edwards said during a radio town hall last month at the University of North Carolina at Chapel Hill. "We, along with others, have stood by and watched it continue."