Wrapping up his Olympics tour, Bush said that in Sunday's meetings with President Hu Jintao and other officials he raised U.S. concerns, including human rights and religious freedoms in China and the situation in Sudan's troubled Darfur region.

"My attitude is if you've got relations with (Sudanese President Omar Hassan al-Bashir), think about helping to solve the humanitarian crisis in Darfur," Bush said in an interview with NBC Sports. "That was my message to the Chinese government."

Support for Sudan -- China is a key investor in its oil industry and Khartoum's biggest arms supplier -- has been among the sources of international criticism of Beijing as the world's spotlight has fallen on it for the Olympic games.

Bush has denounced the Sudanese government for its policies in the Darfur region, where conflict has taken some 200,000 lives and displaced some 2.5 million people since rebels took up arms against the government in 2003.

Bush has called it genocide, a charge the Sudanese government has rejected.

The United States protested to China over its decision before the Games' opening ceremonies to revoke the visa of Olympic gold medallist Joey Cheek, an activist for Darfur.

"Joey Cheek has just got to know that I took the Sudanese message for him (to the Chinese government)," Bush said.

Bush said he also made his case for more religious freedom in China in private talks with the Communist leadership after worshipping at a state-sanctioned Beijing church, and said Hu "listened politely."

"It gave me a chance to say to the Chinese people, religion won't hurt you," Bush said.

"And it gave me a chance to say to the government, why don't you register the underground churches and give them a chance to flourish?"

Bush's four-day visit to Beijing was a balancing act, taking in the Olympic games and praising China on a variety of issues while publicly nudging China to improve its internationally criticised record on human rights.