In life, they became personally and politically estranged. And decades after their deaths, the three Pankhurst women who did so much to win universal suffrage continue to be divided.

While Emmeline Pankhurst, the founder of the suffragette movement, and her eldest daughter Christabel are commemorated by a statue and plaque at the entrance to Victoria Tower Gardens on the south-west corner of the houses of parliament, no such honour has been bestowed on Sylvia, who broke with her family over her opposition to the first world war and pursuit of socialist ideals.

The House of Lords – an institution Pankhurst vowed to tear down in a coming revolution – has over the years repeatedly blocked proposals for a memorial near parliament, despite strong support from figures including the former Commons speaker Betty Boothroyd, and the granting of planning permission by Westminster council.

But while there seems little hope of a statue of the radical pioneer joining her mother and sister in Westminster, an unlikely partnership is seeking to honour her on a plot a few miles east.

The TUC and City of London Corporation are to launch a joint campaign to erect a statue on Clerkenwell Green in Islington in time for the centenary of the Representation of the People Act 1918, which first gave the vote to some women.

The City of London Corporation is providing a grant of £10,000 and has set the TUC the challenge of finding £70,000 to get the project off the ground. The Sylvia Pankhurst Memorial Committee will be announcing two new patrons – the actress Maxine Peake and the former union general secretary Rodney Bickerstaffe – to help drum up support for the cause.

Megan Dobney, a founder member of the Sylvia Pankhurst Memorial Committee and a TUC official, said the Clerkenwell statue would constitute welcome recognition. “Sylvia would not have liked a memorial, but as a symbol of the unsung heroism of thousands of working-class women who fought for the franchise some kind of recognition is long overdue,” she said. “If you go to the park by the House of Lords, there is a statue and a plaque to Christabel and Emmeline. Quite an ugly thing, actually.

A bronze model of the statue of Sylvia Pankhurst by Ian Walters. Photograph: City of London Corporation/Handout

“They have had this for many years but the proposed statue of Sylvia has always been rejected. The reason was that she did not fit in with the establishment of the time by opposing the war. And she was a socialist and an anti-racist campaigner. This statue will correct the historical record.”

A bronze model of the statue has already been made by the late sculptor Ian Walters, who was also responsible for the statue of Nelson Mandela in Parliament Square.

Clerkenwell has been chosen as an alternative to Westminster as it was in the east of London that Sylvia sought to unite the women’s movement with that of the working class, after being expelled from her mother’s Women’s Social and Political Union and forming the East London Federation of Suffragettes.

That initial fracturing of the family over Sylvia’s socialist outlook was to lead to an insurmountable chasm in political outlooks and relations between the women. While Emmeline and Christabel sought the support of the middle classes for their cause and urged their supporters to “do their bit” on the outbreak of the first world war, the East London Federation, uniquely among the women’s suffrage organisations, refused to support the war. Sylvia, who like Emmeline was imprisoned over their campaigns and force-fed while on hunger strike, also wanted the campaign for women’s votes to continue through the war, while her family suspended their’s. The youngest sister Adela emigrated to Australia in 1914, where she founded the Communist Party of Australia.

Christabel was to later urge Sylvia to reconcile “not as suffragettes but as sisters”, but Sylvia would not consider it. “We had no life apart from the movement,” she reportedly told her sibling.

After all women over 21 were given the vote in 1928, Sylvia campaigned on issues such as maternity pay, equal pay and improved childcare facilities.

While describing Sylvia, who died in 1960 aged 78, as both “miraculous” and “unbearable”, George Bernard Shaw once compared Emmeline’s second daughter to Joan of Arc. Many believe the continued campaigning of the East London Federation led by Sylvia was crucial in delivering women the vote.

The announcement of the new site for the proposed statue comes ahead of International Women’s Day on Tuesday. The chairman of the City of London Corporation’s finance committee, Roger Chadwick, said: “We hope this grant is a catalyst for others to come forward to make donations towards this memorial. Sylvia Pankhurst was a remarkable woman. Her work paved the way for London to become the most dynamic and exciting city in the world because of the diversity it welcomes and encourages.

“She knew then what we all recognise today: that our strength comes from embracing and valuing people irrespective of their sex, age, disability, sexual orientation, race or religion.”

The House of Lords – castigated by Sylvia for being “lined up as one man against the emancipation of the proletariat” - claims that permission for a statue in Westminster had not been granted “because the committee was advised that because Pankhurst had no connection to the House of Lords, the statue should not stand in grounds in such proximity”.