Having two women in the contest to decide the next prime minister will make it an honest campaign, former Conservative leader Iain Duncan Smith said.

Home Secretary Theresa May and Energy Minister Andrea Leadsom will battle to win the support of Tory members in the race for the Conservative leadership and the keys to Number 10.

Mr Duncan Smith, who is supporting Mrs Leadsom's bid, said he was pleased that "two strong women" would now battle to become the country's second female prime minister.

In a crucial ballot of Tory MPs Mrs May took 199 votes, to Mrs Leadsom's 84, with Michael Gove eliminated from the race after winning the backing of just 46 colleagues.

On Tuesday Mr Gove won the support of 48 MPs but on Wednesday his campaign manager Nick Boles was forced to apologise after it emerged he had been attempting to encourage Mrs May's backers to vote tactically for the Justice Secretary to stop Mrs Leadsom getting on to the final shortlist of two which will be voted on by party members.

Mr Duncan Smith said a minority would always indulge in "dirty tricks" but having two women in the final stage of the contest would make it "honest" and "straightforward".

He told the Press Association: "I have a simple point: the good thing about having two women go forward is I think we will have an honest, straightforward contest.

"I would like to say to anybody who thinks dirty tricks work: pack it up, because they make you look foolish, make the party look bad and we want a straight, robust contest between two women who know what they are about, who need to present themselves. I am looking forward to that, bring it on."

He added: "I'm proud of my party. We have got two strong women through and this tells the world that this party is an inclusive party.

"It means people like my daughters and others can think to themselves 'there is no glass ceiling, there is no door that is locked against them as women, they can go to the top wherever they are'."

Mr Duncan Smith rejected the idea that Mrs May had wiped the floor with his candidate after securing the votes of well over half of Tory MPs.

He said Mrs Leadsom had gone from a "standing start" after her late decision to run to securing her place on the ballot of party members.

"Theresa May has been standing, pretty much, for some time and has her campaign team all organised. So it's not a surprise if she came first amongst parliamentarians," he said.

"But I believe Andrea now, going to the country, has all that fantastic combination of steel, real grit, real determination, real world experience - working 25 years out of this place (Parliament), setting up charities - and in government she has that experience.

"So I believe all that compassion will come through and people will warm to her and I believe she will win."

He added: "There's no wiping of the floor here. In all the hustings debates, Andrea more than held her own."

Mr Duncan Smith, who quit as work and pensions secretary after a dispute with Chancellor George Osborne over the welfare budget, would not be drawn on whether he hoped to return to the Cabinet if Mrs Leadsom won.

"I am in no way begging for a job, I'm very happy to get on with my life. It's wholly in the hands of whoever becomes prime minister."