Under his scheme, all new candidates for Tory-held and target seats will be drawn from a "priority list" of would-be MPs, of which at least half will be women and "a significant proportion" from minority backgrounds.
But he stopped short of going for all-women shortlists of the kind used by Labour to ensure that particular seats have female candidates.
His announcement came as Prime Minister Tony Blair said voters should judge the new Opposition leader's performance over time, rather than getting caught up by the positive coverage he has received since his election last Tuesday.
"You have got to say 'Well, let's just wait and see about that'," said Mr Blair in an interview on GMTV. "Leadership is about taking decisions, it is not just about being personable."
Tories led Labour in polls published over the weekend for virtually the first time since Mr Blair became leader in 1994.
But the Prime Minister said: "I think you have got to let it be tested over time. Obviously, the media will get behind the guy and give him a big boost... Let's work out and see if he has got these qualities of leadership that you have got to have to do these jobs."
Less white and male
In a speech in Leeds today, Mr Cameron said his desire to make the Tory parliamentary party less white and male had "nothing to do with crude political calculation or crazed political correctness", but was all about "political effectiveness".
"Only if we engage the whole country in our party will our party develop ideas that benefit the whole country," he said.
"The conversation we have in the Conservative Party must reflect the conversation in the country, and the sound of modern Britain is a complex harmony, not a male voice choir."
Mr Cameron's initiative was welcomed by the Fawcett Society, which campaigns for equal representation of women in politics.
"Fawcett calculated after the last General Election that at the current rate it would take 400 years for the Conservatives to reach equal numbers of women and men MPs," said a spokeswoman.
"Today, we hope, the party has moved forward by not just years, but by centuries."
But there were indications that the move may not prove popular among grassroots Conservative Associations, which have jealously guarded their right to select their own candidates.
Mr Cameron today imposed a freeze on selections until his "A-list" is completed, and said that he would only "rarely" allow target seats to pick candidates who do not feature on it.
An online poll of 767 party members for website www.conservativehome.com found that just 35 per cent supported the change.
Source : http://www.dailymail.co.uk/news/article-371402/Camerons-point-plan-women-MPs.html472