Taking on the unions: Kevin Rudd. Credit:Andrew Meares ''The Labor Party came out of the working class and the unions and there are strong and close ties with the party but this is a concerning development and we need to discuss our position on Friday,'' the union leader said. A number of national union leaders, including Australian Workers Union head Paul Howes, publicly endorsed the Rudd reforms on Tuesday. But it is understood unions had been pushing for reforms to go no further than the British model, in which unions retain a third of the votes for the leader. Mr Rudd's reform proposal, to be endorsed within a fortnight, splits the vote 50:50 between caucus and the membership. There is also concern among unions that Mr Rudd is poised to wind back the long-established control by particular unions over Senate seats and upper house seats in state parliaments.

Talks: Paul Howes backs reform, while Tony Sheldon is holding fire. Credit:Michele Mossop For example, a replacement for the Senate seat vacated by Matt Thistlethwaite in his move to contest the seat of Kingsford Smith will be chosen by the AWU. A union source said Friday's meeting would in part try to decide whether Mr Rudd's announcement of Monday was a ''starting point or an end point'' and whether a rule that a change of prime minister would require at least 75 per cent caucus support and proof that the PM had brought the party into ''disrepute'' would place too much power in the hands of the leader. Right-aligned unions likely to attend the meeting include the United Services Union, the Transport Workers Union, the Electrical Trades Union, the AWU and the Rail, Tram and Bus Union. ALP vice-president and TWU national secretary Tony Sheldon said on Tuesday night that caucus should not act on reforms alone.

''Caucus can have a view about these rules just as the Prime Minister has a view,'' he said on ABC's 7.30. ''The Prime Minister and those caucus members are just one voting party member and the party itself makes the decisions about how rules vary when it comes to voting rights of party members.'' Mr Sheldon said he favoured a model similar to the British system. Left-wing unions, including the Australian Manufacturing Workers Union, have fallen in behind Deputy Prime Minister Anthony Albanese, who has been arguing hard behind the scenes in favour of the democratic reforms. Mr Howes, who is known to harbour ambitions of a political career, described Mr Rudd's reforms as ''smart''. ''I've always supported party reform and I think electing the leader through a different mechanism is something that has to happen,'' he said.

Another instrumental figure in the overthrow of Mr Rudd in 2010, Bill Shorten, backed the idea. The Education Minister said: ''It is time to modernise the way the party picks its leaders.'' Loading Former caucus chairman Daryl Melham said the changes would bring stability to the party, saying ''backroom factional hacks'' should no longer be able to pick the leader or decide who got into Parliament. Follow the National Times on Twitter