Harriet Harman has claimed that the arrival in parliament of a fresh generation of “Tory feminist” MPs alongside men with modern attitudes has the power to boost the women’s rights movement.

The Labour MP, who has been parliament’s leading feminist advocate for decades, said the changing nature of female Conservative politicians from the “doughty tweedy matrons” of the past to today’s feminists had been critical. She claimed a newfound cooperation across party lines amounted to a dramatic shift and she welcomed the arrival of men who no longer thought of a woman’s place as being in the home.

“They are the sons of the women’s movement,” she said of political colleagues who had spoken out in recent debates about making parliament more family friendly.

Speaking before International Women’s Day on Thursday and a speech on Tuesday night about her experience as a female MP, Harman said: “The whole agenda for women in the House of Commons has changed, firstly because of the numbers – there are more than 200 female MPs now. But, secondly and critically, there has been a dramatic change in the nature of Conservative women MPs. We have now got feminists on the Tory side, who are very different from the doughty tweedy matrons of the past. These MPs are more modern, and people that we, as Labour women, can work cross-party with.”

Asked to whom she was referring among the Tory feminists, Harman listed Maria Miller, who chairs the parliamentary women’s and equality committee, Nicky Morgan, who leads the Treasury committee, Sarah Wollaston at health, and Theresa May’s parliamentary private secretary, Seema Kennedy. She also praised former education secretary Justine Greening, as well as Anne Milton, Rachel McLean and Mims Davies, and said there were “loads more”.

The comments are a significant shift for Harman, who once branded May as “no sister” on women’s rights, arguing that Britain’s second female prime minister had voted for cuts to programmes that were vital for women.

The MP – who was once mocked as “Harriet Harperson” for her leading role on women’s rights – said it was amazing that there was now so much unity among women in different parties, especially with such fragmentation within politics.

She said there was now potential for female MPs to be a “mighty force” but said they had to follow up with action to boost the fight for equality. “It is no good if women are still tearing their hair out about childcare or facing widespread pregnancy discrimination or suffering domestic violence.”

And Harman pointed to male opinions. “It is also about the change in the attitude of male MPs – the ‘new man’ has arrived in parliament,” she said.

Harman highlighted how Labour’s Darren Jones and Gavin Shuker had spoken alongside the Tories’ Tom Tugendhat and the SNP’s David Linden in a recent debate about giving new parents in parliament “baby leave”. Harman also read out a letter from another SNP politician, Stephen Gethins, after he spoke about his responsibility to his wife.