The MP for Pontypridd resigned as shadow work and pensions secretary last month in protest at Jeremy Corbyn's leadership.Read the full story ›
Angela Eagle has urged Labour supporters to "save" the party, and "heal" the country by signing up to remove leader Jeremy Corbyn.
Ms Eagle has pleaded with opponents of Mr Corbyn to pay the increased £25 fee to challenge his leadership.
Speaking to the BBC, she said: "I would say to the nine million Labour voters out there, there's two days next week when you can actually pay £25, help save the Labour Party, make our democracy work and help me heal our country. Join as a registered supporter.
"Join us in this battle, let us win the Labour Party back", she added.
Ms Eagle also said the membership fee was "pretty good investment for the whole future of democracy".
Jeremy Corbyn addressed thousands of supporters in London after finding out his name will be on the ballot paper in Labour's leadership contest.
Corbyn arrived at a fundraising event at the O2 Forum in Kentish Town, north London, on Tuesday evening, after a meeting with the party's ruling committee.
Supporters said Mr Corbyn was defiant and spoke about the upcoming party election.
Andy Gregg, from St Albans, said: "He reaffirmed our faith in the fact that change is possible. He astonished me by how resilient from the attacks from the establishment he was."
Sorry, this content isn't available on your device.
Jeremy Corbyn won a big victory tonight in his fight to stay on as Labour leader.
The party's ruling national executive voted in favour of his name being put on the ballot paper automatically.
Earlier in the day, Mr Corbyn revealed he had received death threats in the last few days and his challenger Angela Eagle had a brick thrown through her office overnight.
Our Political Correspondent Carl Dinnen reports:
The result of the Labour leadership contest will be announced at a special conference on Saturday 24 September.
The hustings period opens on Friday 22 July and runs until Friday 16 September.
A further timetable of activities will be published on Thursday.
People who joined Labour after February this year will not be allowed to vote in the party's leadership contest, the National Executive Committee (NEC) has ruled.
The freeze date for party members eligible to vote was agreed by the NEC as six months. It means people who signed up recently have been frozen out.
The committee also has agreed that Register Supporters who signed up for the last Labour leadership election will have to sign up again and pay £25 to vote.
They have a 48-hour period from Thursday to Saturday to join and pay the one-off £25 to vote in the contest.
"The NEC meeting has concluded. The timetable for the contest for the Leader of the Labour Party has been agreed by the NEC and will commence on Thursday. The timetable will be published then."
Labour leadership challenger Andrea Eagle says she is determined to win the party's leadership contest, after the National Executive Committee ruled that Jeremy Corbyn would automatically be on the ballot.
Ms Eagle said: "I'm glad Labour's NEC has come to a decision. I welcome the contest ahead. And I am determined to win it."
NEC members wrestled with legal advice over whether Mr Corbyn would need to secure 51 nominations to make it onto the ballot after both sides insisted Labour's rulebook backed their case.
However committee members voted 18-14 in favour of Mr Corbyn in a secret ballot.
Jeremy Corbyn said he is "delighted" that he will automatically be included on the ballot in Labour's leadership contest and pledged to campaign "on all the things that matter".
Speaking outside the Labour HQ at Westminster, Corbyn also said he hoped there would be no legal challenge following victory in the secret ballot by the National Executive Committee.
"I have been elected, last year, 10 months ago today, with a very large mandate. I respect that mandate. It's a responsibility I'm carrying out. I would hope there isn't going to be a legal challenge. There's been a very long legal discussion this afternoon. There were very well-qualified lawyers on hand to advise, so I think we are fine."