These include plans to introduce a minimum wage, legislate against anti-competition business practices and name more political appointees as deputy ministers.

The source said Mr Tien was also expected to state that party leaders would not be able to continue serving in the Executive Council if the chief executive did not change these policies, amend cabinet rules including the collective responsibility system, or increase the role of executive councillors.

The party source said Mr Tien would point out that only the chairman or vice-chairman had the authority to sit in Exco.

It would not toe the government line if Mr Tsang appointed just another regular member to the cabinet.

But the party source said it was unlikely members would withdraw their support for Mr Tsang's campaign for a second term.

It is understood the government is considering appointing Liberal legislator Jeffery Lam Kin-fung to Exco.

Another source, who is close to both Beijing and the government, said the central government's liaison office was concerned by the situation.

'The central government, of course, does not want to see any incident that would affect the smooth course of Mr Tsang's election campaign,' the source said.

'We consider this more a personal rift between Mr Tien and Mr Tsang rather than policy matters.'

Selina Chow Liang Shuk-yee, who is an Exco member, said whether she would serve in Mr Tsang's cabinet in his second term would depend on the party's decision.

'This is not a personal question,' she said. 'Exco is only part of the question. We have to consult party members during the meeting on Mr Tsang's platform. He is saying we should improve relations, but how? This is a problem we have to resolve.'

Party vice-chairwoman Miriam Lau Kin-yee said that while the meeting was primarily called to discuss Mr Tsang's platform, the party's relations with the government leadership were also expected to be discussed.

'There have long been discussions over how to raise our party's relationship with Mr Tsang to a higher level,' she said. 'We don't have to have members in Exco to facilitate better relations. Even if we don't, we can still build a relationship.'

She said that although 'the vast majority' of Mr Tsang's policies in his platform were acceptable to the party, there were clear differences over the minimum wage and the proposed fair competition law.

Earlier, Mr Tien, who has long called for forming a ruling coalition with Mr Tsang, praised him for pledging to raise relations to a new level. The vow was made when he visited party leaders to solicit their support.

But Mr Tien has also made it clear the party will not want any seats in Exco if relations are not improved.

Even if party members were appointed they might not necessarily represent the party and could not guarantee the party's support in Legco for government policies.