The former Northern Ireland secretary, Peter Mandelson, has said he will not damage the government in the run up to the election, but has vowed to continue in his attempts to clear his name.

He told the Independent on Sunday that he was "not seeking revenge" stressing that "nothing I do will ever be designed to harm the government or the party".

But he was adamant that he was not guilty of any wrong-doing over the Hinduja "passports for favours" scandal which led to his resignation. "I know I didn't lie and I have got to establish that,'' he told the newspaper.

The Lib Dem MP who was crucial in exposing Mandelson's involvement in the affair has accused him of deliberately keeping the damaging headlines on the front pages. "He is determined to wreak his revenge and cause problems for the government in the run up to the election. He's trying to say if you are going to sack me, I'm going to try to bring you down'," said Norman Baker on GMTV's Sunday programme.

Baker also said the former Northern Ireland secretary was upsetting the government's election plans. "He's going to come into the TV studios with his own version of events. He's going to keep the story running and he's putting the election back. Tony Blair dare not go to the country until this is sorted out," he said.

Mandelson, who has been abroad in recent days, resigned over a fortnight ago after it emerged he had misled colleagues over his involvement in Indian tycoon SP Hinduja's passport application. He has said he will cooperate fully with the inquiry being conducted by Sir Antony Hammond.