CHINA will screen all 7,000 Hongkong guests attending a charity concert to be staged at the Great Hall of the People in Beijing next Sunday to keep out ''unruly elements''. The concert is to raise money for disaster and poverty relief projects on the mainland. Chinese leaders, including Communist Party Politburo Standing Committee member Mr Li Ruihuan, are expected to attend the ''Relief and Poverty Alleviation Action'' concert. An organising committee has been formed with a vice-director of the local branch of New China News Agency, Mr Zhang Junsheng, as patron. Committee chairman and movie star, Mr Eric Tsang Chi-wai, said yesterday that 7,000 of the 10,000 tickets would be allocated to the territory but a list of guests would be submitted in advance for approval. But he added: ''The Chinese Government will prevent people who are expected to cause trouble from spoiling the charitable event.'' Mr Tsang said the mainland Government had approved more than 20 Hongkong entertainers for the concert, although most of them had attended charity events in support of mainland democracy developments. Stars taking part include singers Alan Tam Wing-lun, Anita Mui Yim-fong and Andy Lau Tak-wah. It is hoped the concert will finance 12 projects providing electricity, water supplies, housing and roads.