Jack McConnell backs David Miliband in Labour leadership race

• Lord McConnell said David Miliband has been "consistently inclusive" but admitted to being "embarrassed" by conduct in the party in the past

Lord McConnell, who will step down as an MSP at next year's Scottish election, said that Mr Miliband would help restore pride in the party and was the "most principled and thoughtful" candidate. He also said that Mr Miliband, considered a front-runner in the election along with brother Ed, understood the needs of devolution.

Mr McConnell added that the party had been guilty of inconsistency in the past, claiming that it has failed to keep up with change in Britain. He said: "We had many successes in Government, but on too many occasions I have been embarrassed by our conduct.

"The greed of individuals, party centralisation and inconsistent policy on the hoof have been damaging, and at times indefensible. And we failed to adapt to the new political landscape of Britain."

But Mr McConnell said Mr Miliband offers the best chance to reverse Labour's problems, adding: "He has been consistently inclusive, he understands the concerns of ordinary people and I believe he is genuinely committed to a multicultural Britain."

"He offers the best chance of a new generation of leader, moving on from New Labour to a new leadership that understands how Britain has changed and how we can change Britain.

"For Scotland, for international affairs and for the regeneration of our movement he is the best choice we can make."

In a statement, Mr Miliband said: "I am absolutely delighted to receive the backing of Jack McConnell.

"Jack is a champion of devolution and serves Scotland with great distinction.

"The Holyrood elections are an important part of Labour's fightback and I will be helping in any and every way I can to win those elections."

The party leadership is also being contested by Diane Abbott, Andy Burnham and Ed Balls.