LOS ANGELES, Feb 12 (Reuters) - Oscar-winning film director Steven Spielberg said on Tuesday he is withdrawing as an artistic adviser to the 2008 Summer Olympics in Beijing due to the Chinese government's policy over Sudan and conflict in Darfur.

"I find that my conscience will not allow me to continue business as usual," Spielberg said in a statement.

"At this point, my time and energy must be spent not on Olympic ceremonies, but on doing all I can to help bring an end to the unspeakable crimes against humanity that continue to be committed in Darfur," he added.

Spielberg is one of Hollywood's top directors, having made blockbuster films ranging from "Jaws" to "War of the Worlds" and "Schindler's List," the World War Two Holocaust drama that earned him an Oscar for best director.

He co-founded the USC Shoah Foundation Institute for Visual History and Education in Los Angeles that is dedicated to the remembrance of the Holocaust.

In April, he wrote a letter to Chinese President Hu Jintao adding his voice to the chorus of people who have protested China's involvement with the Sudanese government over the crisis in Darfur. At that time, Spielberg had asked to meet with Hu, but the president had not responded.

In his statement on Tuesday, Spielberg said Sudan's government shouldered the bulk of responsibility for "these ongoing crimes" in Darfur and said China "should be doing more to end the continuing human suffering there."

China is one of Sudan's major purchasers of oil, among the various ties between the two countries.

Experts estimate that 200,000 people have died and 2.5 million have been uprooted in the Sudanese region's conflict, which started in 2003 and pits mostly non-Arab rebel groups against government forces and Arab militias. The Sudanese government says 9,000 people have died.

The U.S. government has called the violence genocide, but Sudanese officials reject that description and blame the West for exaggerating the conflict.