He explained companies without 50 per cent of their boardrooms being female are losing out on being able to employ some talented individuals.
The prime minister also admitted he had made a mistake by not including more women in his own Cabinet, which currently features Theresa May as home secretary, Justine Greening as secretary of state for international development, equalities minister Maria Miller and Theresa Villiers as secretary of state for Northern Ireland as its only female representation.
While the Cabinet only has four women involved, there are 18 males, which means Mr Cameron is well below the target of 50 per cent of females in the boardroom he has set for companies.
Indeed, almost all of the major roles in the Cabinet have gone to men, with Michael Gove the current education secretary, Vince Cable the business secretary, George Osborne the chancellor and William Hague the foreign secretary.
In a question-and-answer session with workers from Unilever on the 17th February 17, Mr Cameron stated that although workplace inclusion has improved in recent years, there is still much work to do.
“We still have a long way to go. There aren’t enough women around the Cabinet table. It isn’t enough to open up and say you will treat everyone equally. You have to actively go out and encourage women to get involved,” he was quoted as saying by the Daily Telegraph.
The prime minister also highlighted the fact that there are not enough women MPs in the country, with only 47 female Conservative MPs, from a total of 302.
Mr Cameron stated his wife Samantha is often pushing him to further the cause of gender equality and that he agrees with her position on the matter.
Reports recently claimed Mrs Cameron also had the idea of making gay marriage legal, with the bill being passed by the House of Commons earlier in the month.