The MP for Leigh in Greater Manchester, Andy Burnham, has called on his party to support its new leader Jeremy Corbyn.
Mr Burnham came second in Labour's leadership election early this month.
At the party's conference in Brighton he said Mr Corbyn had delivered 'a big moment of change' for our politics.
Leigh MP Andy Burnham has lost the Labour Leadership election to outsider Jeremy Corbyn.
Mr Burnham came second but with just 19 percent of the votes.
Our Political Reporter Daniel Hewitt was at the announcement in London.
The next few weeks are the most important in Andy Burnham's political career.
Ballot papers are now dropping on people's mats and soon they'll vote on whether they want him as the new leader of the Labour Party.
The MP for Leigh is promising something for everybody - nationalising the railways, scrapping tuition fees and thousands of new affordable homes.
But he's trailing Jeremy Corbyn in the polls, and rival Yvette Cooper has called for him to stand down if he is unwilling to attack the frontrunner.
Our political reporter Daniel Hewitt has spent the day with Mr Burnham as he toured the North West.
Andy Burnham says Labour's been too shallow and frightened of its own shadow and he's pledging to change it.
The Leigh MP who is also shadow health secretary is the bookies' favourite to be next Labour leader although there has been a dramatic in support for left winger Jeremy Corbyn.
Andy Burnham is promising "something for people in every postcode".
Leigh MP Andy Burnham is launching his manifesto for the leadership contest later.
A recent poll shows that he's the favourite amongst Labour voters to win.
He believes his plans for the party have 'something for people in every postcode'.
The MP for Leigh Andy Burnham has been addressing a meeting as a new independent opinon poll puts him third in the race for the Labour Leadership.
The popularity of the one time favourite appears to have dipped to 20 percent. He's behind Yvette Cooper and Jeremy Corbyn whose popularity now stands at 42 percent.
The Shadow Health Secretary says members are looking for radical change and don't want a return to Old Labour
The four candidates for the leadership of the Labour Party have appeared together for the first time in the North West since the General Election.
The front runner is still Andy Burnham, the Leigh MP and shadow health secretary, though polls suggest his rivals are closing in.
Our Political Reporter Daniel Hewitt was at the event in Manchester.
Leigh MP Andy Burnham has launched his campaign for the Labour leadership with a pledge to unite the party and the country.
The Shadow Health Secretary used a video message to set out his stall for the top job.