Labour needs to up its game - Andy Burnham
Shadow health secretary Andy Burnham has said Labour needs to "up our game" if the party is to win the election.
The shadow cabinet needed to develop sharper messages and do more to get itself heard, Mr Burnham said.
In an interview with Total Politics magazine, he said it wasn't an issue of leadership but one "of the team".
The Labour frontbencher said the party was "united" and "galvanised", despite recent reports of internal divisions over Ed Miliband's leadership.
Mr Burnham dismissed suggestions he had actively discussed Mr Miliband's exit, but told the magazine it would be "odd" for him to rule out a future leadership attempt.
Mr Burnham, who served as health secretary in the last government, contested the Labour leadership when Gordon Brown stood in 2010, but lost out to Mr Miliband.
'In the battle'
Asked about reports of divisions over the leadership, Mr Burnham said: "It's never good, but it has galvanised people. The mood of the party is very resolute. People are gearing up now to fight the election.
"These things happen from time to time, but fundamentally we are united and in a pretty strong place. That's what matters. The mood of 99% of the Parliamentary Labour Party is very united and very positive."
He said of the shadow cabinet: "I think the time has come for us all to raise our game and support him.
"I don't make this an issue of the leader, I make this an issue of the team. We all have to really up our game, do more to get heard, get our messages sharper, get them over. I see it that way.
"I see it as an obligation. We're in the battle now and it's about fighting every single day."
Pressed on whether he had any future leadership ambitions, the shadow health secretary said: "I can't say what life will throw up in the future, but I'm focused on helping Ed, making Ed the next prime minster and getting back in."
Mr Burnham's comments come after some Labour MPs privately told reporters recently that Mr Miliband was not the right person to win the next general election, taking place in May.
Mr Miliband has admitted that his "mettle had been tested" by the speculation, but he denied that his leadership was a problem.
Mr Miliband said it was the party's "duty... not to shrink from the fight, not to buckle under the pressure but to win".
Asked why the Labour Party was struggling, Mr Miliband said many people were "deeply sceptical about mainstream politics and whether it can solve their problems".