Labour leadership contest: Andy Burnham says he is the only candidate who can prevent 'civil war' in the party

Andy Burnham has claimed only he would be able to prevent "civil war" by uniting the left and right wings of the Labour Party after a bitter leadership campaign.

The shadow health secretary said both left-winger Jeremy Corbyn and Liz Kendall, seen as the Blairite candidate, had "something positive to say" and he wanted a radical agenda to "unite all parts of our party".

He hinted that he would attempt to lure former foreign secretary David Miliband back into domestic politics in order to get "Labour's best team out on the pitch".

Mr Burnham, who has insisted he is the only candidate capable of halting Mr Corbyn's progress before the new leader is announced on September 12, will set out further details of his pitch for unity in a speech tomorrow.

He told Sky News: "What I'm going to set out in a speech tomorrow is that I am the person now that can unite this party going forward. Labour must come through this as a united force, we must not return to factions within the party fighting each other because the last time we did that, in the mid-1980s, we left the pitch clear for Margaret Thatcher to bulldoze her way through Labour communities up and down the country."

He added: "I think all the candidates have had something positive to say, I think Liz Kendall has had something positive to say around devolution, Jeremy has put some really interesting ideas forward about education that have galvanised young people behind his campaign, and I understand that.

"What I want to do is bring all that together and unite it in a radical agenda for Labour going forward, that can unite all parts of our party. That's what I can offer, that is what I can provide now at this stage of this race.

"As those ballot papers land, Labour members do need to think about who is best placed to unite this party of ours coming out of this race. It will change Labour, there is a yearning in our party now for a different way of doing things, a different style of politics."

Mr Burnham said a ComRes poll showing he had the best net rating of the four candidates when voters were asked whether they would improve or damage Labour's chances at the next election was "welcome news".

But none of the candidates performed as well as David Miliband, who lost the 2010 leadership race to his younger brother Ed.

Mr Burnham said he would like the elder Miliband to return from the United States to British politics as part of his plan for Labour unity.

"What I am going to try and do is bring people back into my team that represent all of the shades of opinion in our party, indeed our best talents. I would love to see David come back to British politics.

"I want to involve people in Jeremy's team so that we have captured all of those ideas and that energy that's about there.

"But then we unite with a vision that people can get behind.

"Yes, I want to see everybody, Labour's best team out on the pitch, because this team has now got to take the fight to the real enemy. That's the danger of these contests, if it becomes too inward-facing and Labour loses the focus on our real job of opposing the Government then we will make a big mistake and we will let a lot of people down. I am not prepared to let that happen."

Mr Burnham insisted he had never been a "factional politician" and hit out at the "outrageous" online attacks on his fellow candidates, which have mainly been blamed on backers of Mr Corbyn.

"Some people have been calling other candidates 'Tories' in this race. That is just outrageous, really. Every person in this race is Labour through and through."

Press Association