Kevork Djansezian, Associated Press
Actor George Clooney

George Clooney has put pressure on an Olympic sponsor to speak out over China's foreign policy in Sudan. China is a major trading partner with Sudan, and Beijing has resisted U.N. attempts to force Sudan to accept U.N. peacekeepers in Darfur.

The Hollywood star promotes Omega Watches — one of the worldwide Olympic partners for the Beijing Games.

Clooney has publicly spoken several times about the crisis in Darfur, Sudan, where more than 200,000 people have been killed and about 2.5 million people displaced in three years of fighting between African rebels and government troops.