Senior Labour politicians have begun debating the implications of the party's defeat in the Brent East by-election.

The party lost the previously safe seat last Thursday following a 29 per cent swing to the Liberal Democrats.

Speaking to the BBC on Sunday, home secretary David Blunkett said the government had to "change or die".

"We have got to get back in touch much more readily at the grassroots," he said.

"We have also got to recognise that government means honestly that you get bogged down. You are trying to make a difference, you are trying to change the administration, to change services and that means you don't have the time for listening and campaigning that you used to have.

"And thirdly I think the honest truth is that there has been so much noise going on around us, of course the war, of course the Hutton Inquiry, other things, it is very difficult for people to relate to the kind of messages that we really wanted to get across."

Blunkett added that restoring trust in the government would be a "very big challenge".

"I think if we don't change we die," he said.

"`We are renewing ourselves now. We know we have got to...We need to renew our connection with the electorate so that they know what we stand for, where we are going, above all that we are looking to a new Britain.

"If we are going to have a third term it is about modernising, preparing Britain, helping people with rapid change, dealing with the global economy, but rooting it in the neighbourhood."

Contributing to the debate, the departing Number 10 director of communications, Alastair Campbell, said the government had experienced a "difficult period".

"I think that what has happened is that we have been defying political gravity. And it has maybe gone back to a bit of normality now," he told the BBC.

"Governments go through difficult periods. But the reality is that if governments do the right thing for people's living standards and jobs and public services, they will get there in the end."

Meanwhile, Commons leader Peter Hain said ministers should "show more humility and listen more".

"We need to make sure that we stress all the time that the government is not just about ramming reform down people's throats," he told the GMTV Sunday Programme.

"I think all of these are things that the prime minister has taken on board."

And speaking to the same programme, former Cabinet minister Stephen Byers said Labour needed to rediscover its sense of discipline and unity.

He said it would be a "big mistake" to adopt a "safety first approach".

"It's also a big challenge for the party, not to be self-indulgent but to be united and focused," added Byers.