BRITISH Prime Minister Gordon Brown's problems refuse to go away, much to the chagrin of the leader who took over from Tony Blair not even a year ago. Rebels from within the ruling Labor party on Tuesday threatened to inflict a damaging parliamentary defeat on Brown, further undermining his sagging authority. Brown, struggling in opinion polls, faces a revolt from members of his own party over changes to income tax that are expected to leave some five million of Britain's poorest households - Labor's traditional support base - worse off. Senior party figures warn in-fighting over the tax changes and plans to alter terror detention laws are fuelling discontent among disillusioned voters, who will get the opportunity to pass judgment on the government in local elections next week. The May 1 elections will be closely watched as an indicator of what could happen in a general election with Brown, who succeeded Tony Blair in June, at the helm for the first time. Brown, who served as finance minister for 10 years under Blair, has seen his reputation for sound economic management dented by the effects of the credit crisis and slower growth, and critics now often accuse him of indecisiveness. Failure to quell the rebellion in his party and a poor poll showing next week would only fuel speculation about whether he is the right man for the job. Long-serving Labor parliamentarian Frank Field said he had signed up 39 rebel lawmakers to an amendment to the abolition of the lowest 10 pence tax rate, enough backing to force Brown into an unwanted compromise. “Many of us want to know what the government is proposing to do to ensure that 5.3 million lower paid workers are not made worse off by the budget,” Field said. Labor, roughly half way through its third consecutive term in office, has a working majority in parliament of 67. Field could therefore easily force through the tax compromise if opposition parties support the amendment. Commentators said Brown would face repeated battles with dissident Labor lawmakers over the coming months as his party continues to lag the opposition Conservatives in opinion polls. “Even if he manages to get rid of them on this issue, they'll simply regroup and come back on something else,” Danny Finkelstein, a columnist for the Times newspaper, told BBC radio. One glimmer of light for Brown came on Tuesday in an opinion poll in the Guardian newspaper that showed Labor clawing back some ground from the Conservatives compared with a month ago. The ICM poll put Labor support up five points to 34 percent with David Cameron's Conservatives down three points to 39 percent. The third main party, the Liberal Democrats were down two points on 19 percent. __