Steven Spielberg has decided not to participate in this summer’s Beijing Olympic Games as an artistic adviser, citing China’s lack of progress in resolving the humanitarian crisis in Darfur.

His move is a public relations blow to the Chinese government, which is under pressure to force the government of Sudan to resolve the crisis in Darfur.

Spielberg’s worldwide profile could lead others involved in the Games to pull out and even lead sponsors to reconsider their roles in the event.

As the biggest customer for Sudan’s oil, China has been the target of Darfur advocates for the better part of a year, much to the dismay of Chinese officials who have complained that the Games were being politicized.

“I find that my conscience will not allow me to continue with business as usual,” Spielberg said in a statement released on Tuesday. “At this point, my time and energy must be spent not on Olympic Ceremonies but doing all I can to help bring an end to the unspeakable crimes against humanity that continue to be committed in Darfur.”

Spielberg was to join a team led by Chinese director Zhang Yimou, but outside of a visit to Beijing a year ago, he had done little work on the event. Spielberg even noted in his statement that he has yet to sign a contract that the Beijing Organizing Committee sent to him about a year ago.

“Sudan’s government bears the bulk of the responsibility for these ongoing crimes, but the international community, and particularly China, should be doing more to end the continuing suffering there,” Spielberg said in his statement. “China’s economic, military and diplomatic ties to the government of Sudan continue to provide it with the opportunity and obligation to press for change.”

What remains to be seen is whether other artistic advisers to the Games, such as Quincy Jones and Ang Lee, will continue their involvement. It seems likely that Jones also would decline to participate, given that he has a long history of humanitarian efforts in Africa, as well as a close relationship with Spielberg.

“We haven’t made a decision yet, but obviously we have the same concerns as Steven,” said Jones’ spokesman, Arnold Robinson.

A spokesman for Lee did not immediately respond to requests for comment.

Activists already have been putting pressure on such corporate sponsors to the Games as Coca-Cola, Adidas and Visa.

Spielberg’s role in the Olympics has been in doubt since the spring, when he sent a letter to Chinese President Hu Jintao urging greater action in Darfur. He did not explicitly threaten to end his involvement in the Games, but many surmised that such an option was on the table.

At the time, Darfur activists, including actress Mia Farrow, were urging Spielberg to reconsider his role in the Games, even though the director’s reps say his letter to Hu was unrelated to their criticism. Spielberg had already been involved in humanitarian efforts in the region.

In March, Farrow and her son Ronan wrote an editorial in the Wall Street Journal questioning why the director was participating in the Games, which they termed the “genocide Olympics.”

Farrow, a goodwill ambassador for Unicef, warned that Spielberg risked becoming the “Leni Riefenstahl” of the Games — a reference to the German filmmaker whose images of the 1936 Berlin Olympics amounted to Nazi propaganda.

In the ensuing months, Spielberg and his political rep, Andy Spahn, continued to press Chinese officials; they were encouraged when China agreed to deploy a special envoy to Sudan and then dropped its opposition to a U.N. Security Council resolution to send peacekeepers to stop the genocide.

In addition to letters and phone calls, Spielberg requested a meeting with Chinese officials. In September, he left the set of his latest “Indiana Jones” movie to meet in New York with the envoy and the Chinese ambassador.

“We certainly had the sense they were going to engage Sudan behind the scenes to end the violence,” said Spahn, who was also present at the meeting.

“But the only thing we have to judge by are the conditions on the ground, which continue to deteriorate.”

Spahn said they continued to follow up with Chinese officials, and even met again with them several weeks ago in Los Angeles. But Sudan has continued to resist allowing a peacekeeping force into the country.

“The situation has never been more precarious — and while China’s representatives have conveyed to me that they are working to end the terrible tragedy in Darfur, the grim realities of the suffering continue unabated,” Spielberg said.

In appealing to the Chinese government, Spielberg worked with such industry names as George Clooney and Don Cheadle, as well as the Save Darfur Coalition.

On Tuesday, Farrow called Spielberg’s decision “absolutely great” and said she “couldn’t be happier at a more hopeless moment.”

“This is exactly what China didn’t want — they don’t want their Games sullied,” she said. “This is huge. It is a defining moment for China. China and China alone has the power to influence Khartoum.”

Spielberg did say he still hopes to attend the Games. “It is also my great hope that, with renewed and intensified efforts from China, there will be peace and security in Darfur at last,” he said.

(Winter Miller in New York contributed to this report.)