An angry Caroline Flint waved goodbye to ministerial office on Friday
Labour MP Caroline Flint has been criticised for her attack on Gordon Brown's style of government and his treatment of female ministers.
Ms Flint resigned as Europe minister on Friday, claiming he operated a "two-tier" government via an "inner" circle.
Senior female figures were regarded as "little more than window dressing" by the prime minister, Ms Flint argued.
Fellow MP Geraldine Smith said Ms Flint would "regret" her comments, saying she should have thought twice about them.
'A bit of a strop'
In her resignation letter, Ms Flint said Mr Brown's government was not "inclusive" and suggested she had been ignored when she attended cabinet meetings.
"Several of the women attending cabinet - myself included - have been treated by you as little more than female window dressing." Ms Flint stated.
Her comments have been questioned since less than 24 hours earlier, in the wake of former Work and Pensions Secretary James Purnell's resignation from the cabinet, she had proclaimed her loyalty to Gordon Brown.
As a close friend of former communities secretary Hazel Blears, she had been widely expected to follow Ms Blears' example and resign as soon as polls closed for England's local elections on Thursday night.
But, instead, she insisted she was "proud" to serve Mr Brown and would stay in government.
Geraldine Smith said Ms Flint had been expecting a promotion in Friday's reshuffle and had been disappointed.
"She's been upset and she has had a bit of a strop," she told the BBC.
"She should have counted to ten before she wrote that letter. I think she will regret it."
Deputy Labour Leader and Minister for Women and Equality, Harriet Harman, also rejected Ms Flint's comments while acknowledging "progress" needed to be made in getting more women into senior positions in government.
She said it was untrue that Mr Brown "doesn't take women in politics seriously".
Several high-profile female ministers, including Ms Blears, former Home Secretary Jacqui Smith and housing minister Margaret Beckett, left government in Friday's reshuffle.
But Mr Brown insisted there was still a strong female representation in his cabinet, pointing to the promotion of Yvette Cooper to work and pensions secretary.
Ms Flint has been replaced by ex-MEP Glenys Kinnock, wife of former Labour leader Neil Kinnock.