Environment minister Jane Kennedy has quit the Government in the second round of Prime Minister Gordon Brown's reshuffle.

Ms Kennedy, the MP for Liverpool Wavertree, reportedly resigned after refusing to pledge her loyalty to Mr Brown.

Downing Street said he "regretted" Ms Kennedy's decision to quit the Government but denied he had asked her, or any other minister, for a loyalty pledge.

A source at Number 10 said: "Jane Kennedy has decided to stand down and resign, which happens in reshuffles."

Ms Kennedy was not offered a job, but made it clear she wanted to leave the Government, he said.

Ms Kennedy said she feared Mr Brown would lead Labour to its "bitter end".

"He himself has said in press conferences he had on Friday that he wants to fight on," she said. "My fear is that it will be to the bitter end of the Labour Party.

"I think we are now in such a serious position that we really are fighting for the future of the party."

She said it was a personal decision she had made but that she had wanted to wait until a meeting of the Parliamentary Labour Party later to see what her colleagues were thinking.

Meanwhile, outspoken former minister Frank Field has warned Labour cannot win a General Election with Mr Brown at the helm.

Mr Field, who was one of a handful of Labour MPs who refused to nominate Mr Brown as successor to Tony Blair in 2007.

Writing on his blog, he said that Mr Brown's premiership had been "inept" and Labour's current standing was "pitiful".

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