Left-wing Labour MP Diane Abbott has received enough nominations to stand for the party leadership, it was announced today.
The Hackney North and Stoke Newington MP will stand against former ministers David Miliband, his brother Ed, Andy Burnham and Ed Balls to take over from Gordon Brown.
She reached the necessary 33 nominations after John McDonnell announced earlier today that he was withdrawing from the race.
Voting will take place through September and the successful candidate will be announced before the start of the Labour Party's annual conference on September 25.
Acting leader of the Labour Party Harriet Harman, who nominated Ms Abbott, said: "Over the next few months over four million people will have the chance to help shape Britain's progressive future by choosing the next leader of the Labour Party.
"This will be the biggest and most widespread election of any political party or any organisation in this country.
"The contest will be open, engaging and energising. It will be a chance to invite supporters to join the party to have a vote.
"This debate will involve Labour Party members, supporters in our affiliated trade unions and the wider public. This leadership contest is Labour's opportunity to take forward the rebuilding for our party for the future challenges ahead.
"Over the coming months the candidates will meet thousands of people in meetings across the country and take the debate over Britain's progressive future to as wide an audience as possible."
Paul Kenny, general secretary of the GMB union, said he was "very pleased" Ms Abbott would be on the ballot paper, adding: "This will ensure there is going to be a much wider debate in the hustings.
"There are wide-ranging differences between the candidates on issues such as nuclear and privatisation and it is very important that these are aired."
The Labour Party website revealed that Ms Abbott, Mr Burnham and Mr Balls each received exactly the 33 nominations needed from Labour MPs, while David Miliband amassed 81 and Ed Miliband 63.
Among Ms Abbott's nominators were David Miliband and former leadership rival John McDonnell, who withdrew from the race this morning in the hope of ushering his fellow left-winger on to the ballot paper.
Shadow foreign secretary Mr Miliband pledged last week to lend his nomination to any of the candidates who needed it to ensure they stayed in the race.
In a Twitter message today, he urged supporters to do the same, saying: "Gather John McDonnell pulled out. I'm going now to nominate Diane myself. Encourage others to do the same."
Former minister David Lammy, who was the first MP to nominate Ms Abbott, welcomed her appearance on the ballot paper.
"This is a breakthrough moment for the Labour Party with a diverse range of Labour parliamentarians coming together from across the party to make history," said Mr Lammy.
"I have no doubt that the debate over the coming weeks will be richer for it."
Following the official confirmation of candidates, Ed Miliband said he was now looking forward to "getting out into the country" to make his case.
The shadow energy secretary told Sky News: "I think I am the candidate who can best speak to the values of the Labour Party, best reach out to members of the public right across this country and best inspire people about our party and what we are about."
Mr Miliband said that, whoever wins the election on September 25, the other candidates would be willing to serve under them - and made clear that this includes his elder brother David serving under him if he is successful.
He said it was a "tough decision" to stand against his brother, adding: "I took the decision partly because I thought British politics needs a strong Labour Party and the way we get the strongest Labour Party is to have the widest possible range of candidates.
"I thought I had something to say about this contest, and that's why I'm in it."
Responding to concerns about the lack of diversity in a contest in which all five candidates went to Oxford or Cambridge university and four are white, male former ministers, Ed Miliband said: "In the end, what matters is not where you come from but what you want to do for the country and what you've got to say to the country.
"That's the way the British people are going to judge us and that's the right way to judge people."
Shadow environment secretary Hilary Benn, who backs Ed Miliband, denied the last-minute race to secure enough nominations for Ms Abbott meant the contest had become a shambles.
"It's not a shambles at all," he told BBC Radio 4's The World At One.
"It's going to be a good contest. There's going to be an open political debate because we are not just choosing a leader, we are determining the future of the party."
He said he was supporting Ed Miliband because "he's a unifier and I do believe we have got to move beyond the era of Blair and Brown".
The successor to Gordon Brown will be chosen by a complicated electoral college system in which three sections - MPs and MEPs; affiliated organisations including trade unions; and party members - each wield one-third of the vote.
The postal ballot will be conducted over the summer, with the result announced on September 25 at a special conference ahead of the party's annual autumn gathering in Manchester.
Voters will rank candidates in numerical order of preference on ballot papers, with a "transferable eliminating" system used to redistribute votes until one contender has more than 50% support.
Labour is hoping that interest in the leadership contest will spark a surge in membership applications, with anyone joining the party before September 8 entitled to vote.
Ms Abbott rejected suggestions that she was the beneficiary of positive discrimination, telling the BBC News Channel: "Not at all. I have been an MP for 23 years and if, after 23 years, I haven't earned the right to stand for the leadership then nothing counts for anything."
She denied that it was patronising for David Miliband to lend her his nomination, spelling her name wrongly as "Dianne" in his Twitter message announcing that he had done so.
Mr Miliband was among a number of Ms Abbott's nominators who would not normally be expected to support her left-wing brand of politics, including acting leader Harriet Harman and former ministers Jack Straw, Chris Bryant and Denis MacShane.
Ms Harman has said she will not vote in the leadership election and was nominating the Hackney North and Stoke Newington MP in order to ensure there would be a woman on the ballot paper.
"It's not patronising at all," said Ms Abbott. "There has been a huge surge of letters and emails from party members saying that they wanted a diverse group of people in this leadership contest. David Miliband and others responded to the feelings of the membership.
"This isn't an artificial thing. There is real support out there, both in the party and the public, for the broadest possible slate of candidates and for a proper debate about the future of the Labour Party."
Two opinion polls had found she was the second most popular candidate among Labour voters and one indicated she was the top choice of the public at large, said Ms Abbott.
"My support came from across the party and I believe in the contest I will get support from across the party also," she said.
Ms Abbott said she would stand out from the other candidates because of her "very different view on immigration", her record of opposition to the Iraq War from the start and her determination to recapture the civil liberties agenda from the Tories.
"Above all, having been in the party for 23 years, I know the importance of taking party members seriously and reconnecting with our grassroots," she said.
"I have never been a policy wonk. My parents left school at 14 and emigrated here in the 1950s. I am a single mother and I have spent 23 years working at every level in this party."
And she added: "The important thing is contesting these Tory cuts which will wreak havoc amongst ordinary people in the communities we represent.
"The important thing is to have the best possible debate and then to regroup and lead the battle to protect our communities against Tory cuts."
She dismissed suggestions that her decision to educate her son privately would count against her, saying many voters would empathise with her decision to "put being a mother ahead of being a politician".
Mr Balls sent out a message on Twitter saying: "Very good news for our party that Diane and Andy are on the ballot", while Ed Miliband tweeted: "Really pleased Diane is on ballot, means party can have widest poss choice, ready to get out there and debate across country".
Mr Burnham said he wanted to "speak the everyday language of ordinary people and really put the heart and soul back into Labour".
He told BBC News Channel: "Labour needs to come back to some of its real instincts and that, I believe, is what I can give the party."
In government, Labour allowed itself to appear as if it had been "seduced by power, money and glamour" and was "putting big business before the needs of people", said Mr Burnham.
"Tony Blair rightly repositioned Labour as pro-business, and we should never move off that ground," he said. "But at times it looked as if we had been seduced by power, money and glamour. Really, Labour can never be there.
"When it came to the recession, people out there thought we were looking after bankers instead of ordinary savers and we struggled to get our message over at that point. We have got to learn from all those experiences."
In a hint that he might have raised concerns about the former government's agenda behind closed doors, he said: "To use a football analogy, in the changing room I will make my views very clear but when you are out on the pitch playing for your party, you have got to back the leader and stand behind them loyally.
"Now, when I make my pitch to lead my party, I can really speak with my own voice and say 'These are the kinds of things I would do if you elect me'."
As the son of a telephone engineer father and receptionist mother who was raised in the village of Culcheth, near Warrington, Mr Burnham said he came from a "very traditional Labour background" which would set him apart from the other candidates and made him a "distinctive and different voice" in the campaign.
He told BBC News Channel: "I believe I can give Labour something the Tories don't have and that is a leader that people can relate to, in whose life experience they can see their own and also who can inspire.
"I have had a different route into Westminster and into politics and I have a different background, and I always draw on that background. I will talk in this campaign about how hard it is for kids without connections to get on in the world today.
"I am somebody the Labour movement will be able to see as coming from a very traditional Labour background that gives me a certain grounding in the party and an understanding of the lives of ordinary people. That very much is my pitch."
He said he would press for the establishment of a National Care Service for the elderly as part of his leadership agenda.Reuse content