The Fabian Society general secretary has accused the government of suffering from "neurotic under-confidence".

Writing in a personal capacity on Thursday Sunder Katwala said Labour was "badly stuck" over how to win the next general election.

The head of the leading Labour think-tank called on Gordon Brown to rethink his political strategy, unite the party around a "core vision" and reassemble a "winning electoral coalition".

"The Left worries that countering southern discomfort would cost Labour's soul; the Blairite right flank that appeasing Guardian reading liberals would lose the election," he said.

"Labour won't recover by debating which voters it doesn't want."

He urged the prime minister to "get the Downing Street machine in place, but cancel Number 10's subscription to PR Week".

"Then make a fairer Britain the defining mission," Katwala added.

"Take risks for the cause of child poverty; make clear what climate change demands of us all; go for electoral reform and a written constitution."

The comments came as voters went to the polls in the local and London elections, with Labour prepared for heavy losses.

Brown is widely expected to try to draw a line under the reversals by re-launching his administration with a string of new policy announcements and a new listening tone.

But Katwala warned that the Brown government "risks being written off before its first anniversary".

"The challenge is not just one of communication but political strategy too," he said.

"Gordon Brown recognised last spring that 'more of the same' could not defeat the call of 'time for change' next time.

"He was right. But what three key points of 'change' could voters point to if asked at the end of his first year as prime minister in June?"