A new group to boost women's support for independence is to be launched next month, the Sunday Herald can reveal.

Women for Independence (WIF) will try to close the gender gap in support for leaving the Union and ensure female voices are heard during the constitutional debate.

Opinion polls have consistently shown the challenge First Minister Alex Salmond faces in winning the independence referendum. A recent Panelbase poll found support for independence at 36% and opposition to the policy at 45%.

However, the survey revealed the Unionist lead was partly explained by greater opposition amongst female voters. The snapshot found 62% of women who had a firm opinion were against independence, while only 49% of men were opposed.

Senior SNP strategists privately admit a gender problem exists and concede more has to be done to offer reassurances on social policy and the economy.

It is in this context that WIF, which has 214 supporters already signed up, will unveil its website this week and formally launch in September. The group's ultimate aim is to increase the number of Yes votes amongst women in the referendum.

Jeanne Freeman, a former special adviser in Jack McConnell's administration, is one of the backers.

She told the Sunday Herald: "I want women to be front and centre in this debate. And I want to play my part in persuading other women that not only is an independent Scotland possible, it's the best opportunity we have to realise our hopes and our dreams for our families and our country."

Another supporter, former Scottish Socialist Party MSP Carolyn Leckie, said of WFI: "Currently, fewer women than men support independence. We want to listen to all women and provide a space for discussion about the sort of Scotland we want to live in."

Former SNP candidate Isobel Lindsay is also a key figure in the group. She said: "We know that women are less likely to vote Yes than men in 2014. We want to change that but, first of all, we want to find out what some of the issues are so we can work with women to provide the information they want and, hopefully, persuade them that voting Yes makes best sense for them and their communities' futures."

Natalie McGarry, an independence campaigner who works in the public sector, said of WFI: "We came together because a group of us arrived at the conclusion, individually, that women's voices were missing from both sides of the referendum debate."

Meanwhile, a new group urging trade unionists to back a Yes vote is also being created.

Trade Unionists for Independence will argue that separation offers the only hope of a more socially just Scotland, and a break with a political system corrupted by a capitalist elite in London.

Organiser Derek Durkin, of the Communications Workers Union, said: "Whether independence happens in 2014 or not, it's going to happen, and unless we start organising as a Left, we are handing the tools of the trade to Alex Salmond."

Its creation follows that of Labour for Independence, which was set up last month.