Warren Buffett’s Berkshire Hathaway is the largest U.S. holder of Petro China, whose parent company CNPC (China National Petroleum Corp.) buys more oil from Sudan than anyone else. As a result, Buffett has come under pressure from the Sudan divestment movement to sell his holdings–or at least speak out loudly against the genocide in Darfur.

I blogged about Buffett recently, but decided to rewrite the blog post as a CNNMoney column after pressure from Mia Farrow and Steven Spielberg apparently persuaded a high-ranking Chinese official to speak out against the genocide. Amazing. If they can make a difference–Spielberg’s got ties to China because he is making a movie about the 2008 Beijing Olympics–maybe Buffett can, too. Here’s how the column begins:

Could Warren Buffett’s Berkshire Hathaway be helping to support genocide in Darfur?

The Sudan divestment movement, which has persuaded dozens of universities and state governments to sell holdings of companies doing business in Sudan, says Berkshire should do the same. Buffett is resisting. The legendary investor will tangle with his critics over the issue on May 5 at the company’s annual meeting in Omaha.

It should be a fascinating debate. Berkshire has become a target of the divestment campaign because it owns 2.3 billion shares of PetroChina Co., a subsidiary of the state-controlled China National Petroleum Corp. (CNPC). CNPC has extensive operations in Sudan; it owns a major stake in Sudan’s national oil consortia.

You can read the rest here.