London, June 5 (IANS) A fourth British minister resigned in four days Friday, spurring Prime Minister Gordon Brown to begin reshuffling his cabinet in the middle of a deepening political crisis.
Pressure mounted on Brown to quit after John Hutton resigned as defence secretary, following the shock resignation of James Purnell as work and pension secretary late Thursday night.

Purnell, considered a Labour high-flier, told Brown in a strongly-worded resignation letter: “I now believe your continued leadership makes a Conservative victory more, not less likely.”

The latest resignation came as Labour faced the prospects of heavy mid-term defeats in local municipal elections held Thursday.

Two other cabinet ministers - Home Secretary Jacqui Smith and Communities Secretary Hazel Blears - have quit this week in addition to two junior ministers amid a spreading political scandal over dubious expenses claimed by MPs and ministers from taxpayers’ cash.

Although Hutton said he was stepping down because he was “leaving frontline politics” and that he would continue to support Brown, calls grew nevertheless for the prime minister to resign.

“People will be asking ‘what has happened to the authority of the government, what has happened to the prime minister’,” said opposition Conservative Party leader David Cameron, calling for general elections.

“It’s terminal for Gordon Brown. It looks like they (Labour) have lost interest in the public and the public have lost interest in them,” said Sarah Teather of the Liberal Democrat Party.

Brown has till the summer of 2010 to call general elections but British political observers said he may be forced to call them much earlier if the Labour rebellion grows.