``We don't know the limits of Chinese government tolerance for groups such as ours, but we think it is important to be here during the summit,'' John Ackerly, president of the International Campaign for Tibet (ICT), said Wednesday.

``We have come to Beijing to ensure Tibet remains in the mainstream of Sino-US discussions.''

``Tibet is higher on the agenda of the US administration and the Congress than at any time since the US normalised relations with China, reflecting widespread opposition to Chinese rule in Tibet and growing support for Tibet with the US public,'' he said.

Ackerly and another ICT member arrived in Beijing on tourist visas on Monday, and are staying in the same hotel as the US delegation.

They had already contacted the US embassy which was ``not overly pleased'' to see them in China, Ackerly said.

ICT hasrecently collected 200,000 signatures on a petition calling for Tibet to be at the top of Clinton's agenda in his meeting with the Chinese leadership.

``President Clinton needs to urge China to agree to talks with the Dalai Lama or his representatives as strongly as Secretary of State Madeleine Albright did in her May trip,'' Ackerly said.

``Talks are possible and are in the interests if China, which will otherwise face a protracted and bitter struggle in Tibet for decades to come,'' he added.

China, which claims a long history of sovereignty over Tibet, sent troops to `liberate' the region in 1951. Eight years later, the Dalai Lama, who is Tibet's top spiritual leader, fled to India after an abortive uprising against Chinese rule.

China maintains that it will only enter discussions with the Dalai Lama over Tibet's future if the Dalai Lama accepts that Tibet is part of China.