The government has published new legislation to allow women only shortlists for the selection of parliamentary candidates.

Labour's move to improve the representation of women in parliament follows recent decisions by both the Tories and the Lib Dems to reject women-only rules as "tokenism".

Demands for positive action to increase the number of female MPs were boosted by general election research by the Fawcett Society that found 86 per cent of Conservative candidates, 79 per cent of Liberal Democrats candidates and 77 per cent of Labour candidates were men.

Launching the new bill, the cabinet minister for women, Patricia Hewitt argued that women needed a "greater influence on decisions made in our society".

"We want to ensure that parliament becomes more representative by knocking down the invisible walls that prevent women coming through. This bill is a large part of that process," she said.

The DLTR secretary Stephen Byers presented the Sex Discrimination (Election Candidates) Bill to MPs on Wednesday.

The bill will exclude "certain matters relating to the selection of candidates by political parties" from the operation of the Sex Discrimination Act 1975.

"This is a practical bill designed to remove the constraints on political parties who want to take positive measures to increase the representation of women," he said.

The legislation will revive the women-only shortlists credited for the high number of female Labour MPs elected to the Commons in 1997.

Amid great controversy in 1993, the Labour Party adopted all-women shortlists in a number of constituencies with a good chance of returning an MP.

But the policy was challenged by two male Labour candidates at an industrial tribunal which ruled that it breached the Sex Discrimination Act 1972 and Labour abandoned the policy in February 1996.

The legal setback decision did not affect the 34 women already selected under the women-only rules, contributing to the record number of 120 women MPs elected in May 1997.

Legislation is regarded as vital by many senior Labour figures in order to empower "groups in our democracy that are not getting through".

And Labour's chief whip Hilary Armstrong recently told ePolitix.com that positive action was needed to tackle the institutional sexism that existed in political parties - including her own.

Branding Labour's current quota system as a failure, with just three women among June 2001's intake of new MPs, she blamed the "networking" of male party activists for the shortfall of females.

"It was supposed to be 50/50 on every shortlist but the experience was that constituencies put on women they knew couldn't win whilst they kicked off anyone who was going to be a threat to the favourite son," she told ePolitix at Labour's conference.

"What we now know in the Labour Party, because we've been through it, is that unless you've got positive measures then the networking of the unions, the networking of the men, has sorted it out so that very good women are not getting a look in," she said.

Both the Tories and the Lib Dems have ruled women-only rules, opting for the kind of quota systems Armstrong argues have failed for Labour.

In an ePolitix interview in July, Iain Duncan Smith triggered controversy when he argued that "all-women shortlists have not been a success for Labour".

"Instead of getting people who are high quality, what we've actually got in is people who haven't really performed as politicians for the Labour Party," he said.

And at the Conservatives' Blackpool conference the party's chairman, David Davis, said it would be "decent policies" that would attract more people to an inclusive Tory party. "Not by quotas or gestures that undermine the very principles of freedom and equal opportunity for which we stand," he said.

At the Lib Dems conference delegates angry at "tokenism" rejected a women-only motion backed by the party's leadership.

The party instead set a 40 per cent target for the number of women selected in the party's most winnable seats and those where a sitting Lib Dem MP is standing down.