Speaking to ITV News, David Blunkett has told those criticising Ed Miliband to "get off your bum, and get out there and campaign."
The veteran MP - who has announced he is standing down - said: "My message to people who are chipping away at Ed Miliband: forget the idea that someone else is going to step forward or there's going to be some kind of peremptory election. There isn't.
"So get off your bum and get out there and campaign. Not for any individual but for the values we espouse."
Mr Blunkett added that if Labour were to lose next year's election they could be out of power for a very long time.
The Rt. Hon. David Blunkett, Member of Parliament for Sheffield Brightside and Hillsborough, announced to his constituency annual meeting, last night, that he would not be seeking re-election.
Mr Blunkett , who is 67, said it was clear that Ed Miiband would want "new faces in ministerial office and a clear break with the past" if Labour won next year's election.
He said in a video statement on his website that standing down has been the 'most difficult decision' he has had to make and he has 'loved serving the people of Sheffield.'
Mr Blunkett, who is blind, was first elected as MP for the Sheffield Brightside seat in 1987 and served as education secretary, home secretary and work and pension secretary under Tony Blair.
Labour MP Mike Gapes, David Blunkett's one-time Parliamentary private secretary, said:
Former Labour Olympics minister Tessa Jowell said:
Former Enviornment Secretary Hilary Benn paid tribute to Blunkett's "passion for justice":
Ed Miliband said David Blunkett had been a "huge asset" to Labour and will be "hugely missed", after the former home secretary announced his decision to leave parliament.
"David Blunkett is a man whose commitment and determination have carried him to the highest positions in politics with one purpose: to serve the people of our country. He will be hugely missed," Mr Miliband said.
"He has been a friend to me during my time as leader. I have valued and counted on his advice and wisdom. Every Labour leader under whom he served would have said the same. He is Labour through and through.
"David can take great pride in all he has done to improve the lives of people in this country. He has been an amazing asset to the Labour Party and to Britain and I know he will continue to serve the country and the Labour Party with great distinction."
David Blunkett said Ed Miliband would want a "clear break from the past" if Labour won next year's general election, as he announced his decision to step down from Parliament.
Mr Blunkett, who will leave his Sheffied Brightside seat at the next general election, admitted to party members that standing down was his "most difficult political decision".
Former home secretary David Blunkett is to stand down from Parliament at the next general election, he has announced.
Jurors have been played furious voicemail messages left by former Home Secretary David Blunkett in the wake of false press claims about his relationship with a female friend.
The Old Bailey was played recordings from the autumn of 2005 in which the politician said he hoped whoever had leaked information to the media would "rot in hell".
The voicemails were left on the mobile phone of Sally Anderson, a former estate agent who befriended Mr Blunkett in 2005.
In one message left on Ms Anderson's phone, he said: "Someone very, very close has done a really phenomenal piece of work on destroying both our lives at this moment in time and it's vile."Whoever it is I hope they rot in hell."
It is claimed that the messages were illegally accessed on behalf of journalists at the now-closed tabloid the News of the World (NotW).
The former home secretary David Blunkett said Britain's intelligence laws should be reviewed in the wake of the eavesdropping row, to stop spy agencies getting "carried away".
Speaking to The Guardian, Mr Blunkett said:
"Human nature is you get carried away, so we have to protect ourselves from ourselves. In Government you are pressed by the security agencies. They come to you with very good information and they say, 'You need to do something'.
"So you do need the breath of scepticism, not cynicism, breathing on them. You need to be able to take a step back.
"If you don't have this, you can find yourself being propelled in a particular direction."
He said a high-level review by specialists was the best way to update laws.