Patricia Hewitt last night defended her decision to send an e-mail to fellow Labour MPs calling for a vote on whether Gordon Brown should be the party's leader.

The Leicester West MP argued that she made the move – which only gained limited support – because "constant speculation" over whether Mr Brown would remain at the helm was damaging the party's chances of election victory.

She also claimed the views of Labour members and voters in Leicester had motivated her to make the call, which she did with former Defence Secretary Geoff Hoon in an e-mail sent out at 12.26pm yesterday, as Prime Minister's Questions was drawing to a close.

The former health secretary asked her party members to back or sack the Prime Minister to end questions over his position "once and for all".

But other Labour MPs, angry that Ms Hewitt had taken action just as the party was kicking off an election campaign, accused her of having an "ego" and not putting the interests of the party first.

Ms Hewitt rebutted the accusation, saying: "For most of the last two years there have been public and private calls for Gordon to go.

"On Tuesday, the first day of Parliament, there were immediately rumours of an attempted coup and that a minister would resign.

"The real danger now is that we have another three to four months of public and private opposition, when it would be better to have a secret ballot to find out whether there is appetite for a leadership contest."

If a ballot showed there was no desire for a contest, said Ms Hewitt, the party would be able to move on from the leadership issue. Otherwise a contest would be held.

She added: "I want to make clear we are not calling for Gordon Brown to stand down. We are calling for MPs to be given a chance to have a say in the future of the party."

Leicester South MP Sir Peter Soulsby said: "It was astonishing timing. I simply can't understand it."

He added: "There is no sense at all that there is any sort of following here. It looks like a private enterprise with little support."

Lougborough's Labour MP Andy Reed was unavailable for comment. In the city, Leicester East's Labour MP Keith Vaz said he would not comment. Ms Hewitt said she and Mr Hoon had come to the conclusion that something needed to be done separately and only decided to act together after having a chance conversation on Monday.

Ms Hewitt denied she had discussed her call with other potential leadership candidates or outspoken rebels. She said a secret ballot to decide whether there could be a leadership contest might be held within a week, if there was support.

Eric Pickles, the Tory party chairman, said: "We cannot go on like this.

"The only responsible thing the Government can do is call a general election."

Ms Hewitt, the city's first female MP, was elected in 1997 but last summer announced she was standing down at the general election for "personal reasons".

In 2005 she was health secretary but when Mr Brown took over she stepped down from the cabinet.