The five members, including Health and Welfare's Dr Leung Chi-chiu, are at grade D1 or D2 positions. They were barred from sitting on the committee by government guidelines issued on Tuesday.

The guidelines stipulated that senior officials (at directorate grade, or administrative officers), information and police officers may not serve on the Selection Committee, in order to maintain political neutrality and avoid any conflict of interest. But the guidelines did not discuss the provisional legislature.

An association spokesman, Ma Siu-leung, maintained yesterday it was their right to participate and denied it was a move to confront the Government.

Chairman Hui Kwok-hung said the Government had not allowed enough time for negotiation and this was regrettable.

'The association has all along voiced our opinion of wishing to take part in the committee,' he said. 'But the guidelines were released just one day before the nominations started.' He said Secretary for Civil Service Lam Woon-kwong had yesterday told him the guidelines would not be amended.

Mr Hui said it was right to impose restrictions on the election of the provisional legislature since it would involve 'dual loyalty'. But for the selection of chief executive, there should be no restrictions at all, he said.

A spokesman for the Civil Service last night said the branch regretted the association's decision. But he reiterated it was important that civil servants should refrain from overt political activity.

He said members of the Selection Committee would 'accept the role of choosing a candidate for chief executive and of choosing people to serve on a provisional legislature'.