David Cameron has been told to stop "tiptoeing" around and get on with appointing more women to his cabinet, amid Westminster rumours that Theresa May is positioning herself to become the party's second female leader.
On Sunday evening Sarah Wollaston, the MP for Totnes, said the prime minister's inner-circle was "far too posh, male and white" and warned that he was "running out of time to fix it".
She Tweeted: "I consider myself a Cameron loyalist; he is the best person for the job but should listen to critical friends.
And appearing on Sky News on Monday, Wollaston said the cabinet needed to more accurately reflect the population.
"If we look at proportion of women in cabinet and the proportion of ethnic minorities in cabinet it doesn't reflect modern Britain," she said. "Stop taking about it and get on and do it."
Wollaston added: "If you look at the women who there are in politics today, there are plenty of talented women he could choose from."
Epping Forest MP Elanor Laing said all the efforts made further down the food chain to increase the number of women in politics were a waste of time if the prime minister did not use his powers to appoint more women to top jobs.
"We have been tiptoeing around this issue for decades," she told Sky News. "Basically there is only one person who can make a difference to putting women in places they are seen and reflect the current Conservative Party, the country and government and that's the prime minister."
"There is only one person who can grasp this and change the image of his government and that's the prime minister."
Frustration at the lack of progress made in getting more women in to top political jobs, only four members of the current cabinet are women, comes amid suggestions that one of them, the home secretary, is plotting to take over from Cameron should he be forced out either before or after the 2015 election.
May was hailed as having ""fantastic credentials" by one of the other female cabinet ministers, culture secretary Maria Miller, after the home secretary delivered a wide-ranging speech at the weekend that set out her vision for the party.
Former defence secretary Liam Fox, who is often accused of having his own leadership ambitions, has warned Tory MPs that launching a coup against Cameron before 2015 would be "madness".
Were May to succeed Cameron as Tory leader she would be the party's second female leader, following in Margaret Thatcher's footsteps.