Labour 'fixing' leadership race, says John McDonnell
John McDonnell: 'It's going to be very difficult to get on the ballot paper'
Left-wing Labour MP John McDonnell has accused the party of "fixing" the race to succeed Gordon Brown as leader.
He said he wanted to stand but would struggle to get the backing of the 33 MPs he needed to get by next Thursday.
Jon Cruddas - who ruled himself out of the race on Monday - also said it was not long enough for MPs to make up their minds.
Only ex-ministers, and brothers, Ed and David Miliband have so far said they will stand for leader.
Former Schools Secretary Ed Balls and former Health Secretary Andy Burnham are also thought to be considering a bid.
The result of the contest is due to be announced on 25 September, Labour's ruling National Executive Committee (NEC) has decided.
But MPs who want to stand must gather 33 signatures of Labour MPs by 27 May, under the timetable announced by the party on Tuesday. They can then gather "supporting nominations" over seven weeks from constituency parties and unions.
If the Labour Party wants an open, all-encompassing debate over its future, and a great variety of choice in who is to lead the party, then it is going about it in a very strange way
Mr McDonnell, who wanted to stand against Gordon Brown for the leadership in 2007 but failed to receive enough nominations from MPs, said it was wrong to reduce the period for nominations to four days, from 24 to 27 May.
He said this was not enough time for the many newly elected Labour MPs to weigh up the merits of different candidates and for potential contenders to canvass for support - although he said he was still determined to try.
"I think it undermines the democratic process from the outset," he told the BBC News Channel.
"I thought we had learnt those lessons."
By "curtailing" the nomination process, Mr McDonnell said Labour officials were effectively "fixing" the contest in favour of establishment candidates such as David Miliband.
"It prevents people like me coming forward and securing nominations," he said.
'Ed, Ed and David'
The Hayes and Harlington MP said the Conservatives and Liberal Democrats had held more open contests when they elected David Cameron and Nick Clegg as their leaders.
And influential backbencher Mr Cruddas - who was among those expected to stand and came third in the Labour deputy contest in 2007 - told the BBC he did not think it was long enough to gather signatures.
"These guys, if it's Ed, Ed and David, they have been ministers since the day they were MPs. I have known some of them for 20 years but I don't know what they stand for and I won't be able to make up my mind, I doubt, in nine days' time.
"I think we should extend this, crack it open, re-enfranchise the party and allow them to define what they are."
There has been anger within sections of the party that Mr Brown was elected without a contest in 2007.
Mr McDonnell, who chaired the Socialist Campaign Group of Labour MPs in the last Parliament, is a leading voice on the left of the parliamentary party.
Mr Balls and Mr Burnham are thought to be weighing up their options amid calls for the contest to be as competitive as possible.
Several senior Labour figures have ruled themselves out, including acting leader Harriet Harman and former Home Secretary Alan Johnson.
The new leader will be elected by a ballot of Labour MPs, MEPs, party members and members of affiliated organisations such as trade unions and socialist societies.
Ms Harman has defended the election rules, saying they will lead to a "dynamic" contest, with up to four million people eligible to vote.
The ballot will take between 16 August and 22 September, with the result being announced on the first day of the party's conference in Manchester.
Hustings will take place in June and July, with some backbench MPs pressing for the candidates to square up in a TV debate.
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