Former Labour cabinet minister Ed Balls said today he intends to run for the leadership of the party.
"I'm going to put my name in for the party leadership," Mr Balls said today. "There'll be time for speeches in due course.''
Earlier today left-winger John McDonnell joined the race to lead the opposition party, calling on trade unions and party members to support his bid to return Labour to its roots.
The centre-left party is searching for a new leader to succeed former prime minister Gordon Brown, who resigned after the party lost its 13-year grip on power in the May 6th election, and a Conservative-Liberal Democrat alliance now governs Britain.
Mr Brown's predecessor, Tony Blair, moved the traditionally working-class party to the centre in the 1990s, calling it "New Labour" and winning three elections in a row, but this month's defeat has left the party searching for a new direction.
"I believe (New Labour) lost the moral basis of the Labour Party as it was founded . . . the creation of a fair and just and peaceful and equal society," McDonnell said in a rousing speech to the Public and Commercial Services union.
Mr McDonnell (58), who is not well known outside the party, is viewed as an outsider in the leadership stakes, but he has support among the unions, Labour's biggest financial backers.
The frontrunner in the race is David Miliband (44), foreign minister under Mr Brown. Once an adviser to Blair, he is seen as the candidate of the party's "Blairite" or centrist wing. His brother Ed Miliband (40), a former energy and climate change minister, is also contesting the leadership election.
His supporters say he is a unity candidate who would end years of tension between the so-called "Blairite" and "Brownite" wings of the party.
Labour has given itself four months to elect a new leader. Balloting will run from August 16th to September 22nd, and the winner will be announced at the annual party conference on September 25th.