'If it was one man, one vote, or one man, two votes, so long as everyone had two votes, that would still be a fair and equal principle,' Tang told a caller who had drawn him into a debate over whether complying with the principles of 'universal and equal suffrage' necessarily meant the abolition of those seats.

When another caller criticised the government proposal as violating the Basic Law because it failed to pave the way for functional constituencies to be abolished, Tang said: 'The Basic Law says we must abolish functional constituencies? Which article?' In any case, Tang said, this administration was not authorised to deal with electoral arrangements other than those for 2012.

But critics pointed out that as a frontrunner for the top post in 2012, Tang could be the person who will lead the debate on whether functional constituencies should stay. They also noted that Tang spent seven years as a legislator without ever being directly elected.

Civic Party leader Audrey Eu Yuet-mee said the party had always maintained the models for universal suffrage should be fixed now, to avoid the conflict of interest that would arise from having the chief executive who is chosen in 2012 steering the debate on electoral arrangements that would determine his own re-election in 2017.

After further digestion of the government proposal, pan-democrats also said that instead of committing to the abolition of functional constituencies, the government seemed to be thinking of ways to preserve them.

Tang's comments seemed to diverge from a statement by Secretary for Constitutional and Mainland Affairs Stephen Lam Sui-lung that the government had 'no stance' on whether modified functional constituencies would comply with the principle of universal and equal suffrage.

But taken with Chief Executive Donald Tsang Yam-kuen's comments last month that the functional constituencies could not comply with those principles 'in their present form', they suggest that plans might be afoot to keep the trade-based seats in a different form.

The abolition of functional constituencies has long been a priority of the pan-democrats, who argue that the legislature's power to scrutinise the government is hampered by having half its members accountable to only select sections of the community and yet holding an effective veto power due to the voting procedures.

Currently, all 3.3 million registered voters can vote for the 30 geographical constituency lawmakers, but only 210,000 individuals can vote in the functional constituencies. And nine of those seats are returned by corporate bodies, not individuals.

Only people in certain professions, or with certain business associations, can stand for functional constituency seats - a situation that would not be rectified even if all registered voters could vote for functional constituency lawmakers.

It was not clear yesterday how a system of one man, two votes would differ from the one introduced in 1995 by then governor Chris Patten.

That scheme, which enraged Beijing and was scrapped after the handover, gave every working person a vote in a functional constituency and a geographical constituency.

Article 68 of the Basic Law states that 'the ultimate aim is the election of all the members of the Legislative Council by universal suffrage'.

In an RTHK programme yesterday, Lam said the government was 'freezing' the functional constituencies in their current form. 'We don't want to increase these traditional functional constituencies,' he said, arguing that adding new seats for district councillors would increase the mandate of that chamber.

The Law Society and the Bar Association questioned the logic of introducing more functional constituency seats, even ones held by district councillors. These 'obviously must fail to comply with principles of universality and equality', they said, and would be a 'retrograde step' in achieving universal suffrage, which necessarily meant abolition of the functional constituencies.

British consul general Andrew Seaton said he hoped the final proposal to be tabled next year would be sufficiently progressive to achieve the required two-thirds majority of lawmakers. The US consulate called for substantive dialogue among concerned parties in the consultation.