Just one day after a Wall Street Journal report that Warren Buffett is buying shares of Kraft Foods, we get word today that he's sold a small slice of his stake in PetroChina, the big Chinese oil company that's been linked by human-rights activists to the genocide in Darfur.  PetroChina's government-controlled parent has "extensive involvement" with Sudan's oil industry.

The AP reports there's "no indication whether he was responding to demands by activists to cut his ties to the company due to its investments in Sudan."

But the very small size of the sale, about 17 million shares worth just $27 million, appears to me to be a slight adjustment rather than any kind of message.

Dow Jones Newswires quotes unnamed analysts as saying Buffett "apparently sold part of his stake to lock in some profits" following a big gain in PetroChina's share price.

Andy Knoblauch at All Things Buffett, however, hints the sale might be connected to the Darfur controversy.

At the Berkshire Hathaway annual meeting in May, shareholders rejected an call to divest from PetroChina and Mr. Buffett said: "PetroChina in no way tells the Chinese government what to do.  We have no disagreement with what PetroChina is doing."

Buffett remains PetroChina's second largest shareholder with 10.96%.  Before the sale, his stake was 11.05%.

Questions?  Comments?  Email me at buffettwatch@cnbc.com