BEIJING, June 13 (Reuter) - China said on Thursday it had ordered a German political foundation to stop all activities in China, one day before the group holds an international conference on Tibet in Bonn.

The Naumann Foundation, closely linked to Germany's Free Democratic Party of Foreign Minister Klaus Kinkel, had openly supported the "splittist activities" of the Dalai Lama and interfered in China's internal affairs, Foreign Ministry spokesman Shen Guofang said.

"It ignores repeated representations by the Chinese side and insists on activities that interfere in China's internal affairs," Shen told a regular news briefing.

"The Tibetan issue is China's internal affair," he said, adding that Beijing had called in the German ambassador to express its concern.

Naumann's four-day conference is to begin on Friday and features an appearance by the Dalai Lama, whom Beijing accuses of trying to split China and of fomenting anti-Chinese unrest in the Himalayan region of Tibet.

The foundation had appealed for public money to finance the conference after Bonn withdrew a pledge of $190,000 following complaints from China.

Bonn said it could not back a conference event billed as including members of Tibet's government-in-exile.

About 250 participants from 53 countries were expected to take part in the conference in Bonn.

"We decided to suspend the cooperation between the State Statistics Bureau and the Naumann Foundation and halt all the activities by its representative in China," Shen said.

Naumann had cooperated with China on several educational programmes for Chinese officials.

Officials at the foundation and the German Embassy were not immediately available for comment.

"We hope the German government can take concrete action to prevent certain people in Germanay from doing things to interfere in China's internal affairs," Shen said.