Theresa May has promised to be “bloody difficult” during Brexit talks with the European Commission president while speaking at a hustings for Tory MPs before the second round of voting to choose the party’s new leader.

Referring to unguarded comments recorded by Sky News by Tory former chancellor Ken Clarke, in which he referred to Mrs May as "a bloody difficult woman", the Home Secretary joked that the next person to share his view would be Jean-Claude Juncker.

“Ken Clarke might have found me to be a 'bloody difficult woman'”, said Mrs May. “The next person to find that out will be Jean-Claude Juncker”, she added with her response receiving cheers from MPs, ITV reports.

The hustings also saw Andrea Leadsom, who came second in the first round of voting in the party’s leadership race on Tuesday, say that she would not be releasing her tax returns, as other candidates have, unless she made the run-off on Thursday.

The minister told MPs they could come to see a summary of her tax affairs personally if they wanted to.

The favourites in the Tory leadership race Show all 5 1 /5 The favourites in the Tory leadership race The favourites in the Tory leadership race Theresa May The longest-serving Home Secretary in 100 years took a back seat in the referendum campaign. While backing Remain, she did not hit the campaign trail and delivered only a handful of speeches and interviews, and was critical of many aspects of the EU, particularly the European Convention on Human Rights. Hedging her bets allows her to now emerge as a ‘unity’ candidate, and she is said to have been building up her back-room staff in preparation for a leadership bid. She has the significant advantage of having served in one of the great offices of state, in a steady and competent manner that has won her many admirers within party and the civil service. At a time of great instability, it may be that she is viewed as steady hand on the tiller. Mrs May does however, lack the ‘star quality’ of a Boris Johnson and party members may doubt her ability to connect with ordinary voters PA The favourites in the Tory leadership race Michael Gove The Justice Secretary may be able to set himself up as ‘the thinking Tory’s Brexit candidate’. Made an enormous political and personal decision to back Leave, taking on his old friend David Cameron. He performed well during the TV debates, and will be an admired figure among Eurosceptic Conservatives. Along with Johnson, he will be hindered by the fact that he led a very divisive campaign, characterised by ‘blue-on-blue’ action. MPs may also judge that he lacks Boris Johnson’s wider appeal with the electorate. Possibly more likely that he will settle for being his new bosom buddy Boris’s Chancellor Getty The favourites in the Tory leadership race Stephen Crabb Highly-rated Work and Pensions Secretary, raised on a council estate, so could reach out to non-traditional working class Tory voters Getty Images The favourites in the Tory leadership race Andrea Leadsom Minister of State for Energy at the Department of Energy and Climate Change is one of the most prominent figures in the Leave campaign, seen to have performed well in TV debates Rex Features The favourites in the Tory leadership race Liam Fox British Conservative MP and former Secretary of State for Defence, as sources said he will stand for the leadership of the Conservative Party AFP/Getty

Michael Gove, who fished third in Tuesday’s vote, was questioned over what some MPs see as his "betrayal" of Boris Johnson, but the Justice Secretary said he had decided to run because he thought the former-London mayor was not suited for the job.

He was also challenged over a text sent by his campaign manager urging Ms May's supporters to vote tactically in the second round of voting in the Tory leadership battle on Thursday in order to block Ms Leadsom from the final run-off.

Theresa May admits future of EU citizens living in the UK is uncertain

Campaign manager Nick Boles has since been forced to apologise after the text was leaked and said over Twitter that Mr Gove “did not know about it let alone authorise it”, adding “it does not reflect his views.”

The Home Secretary is expected to be confirmed on Thursday as one of the two contenders chosen by MPs to go forward in a vote of around 150,000 Conservative members to elect a new leader - and prime minister - on 9 September.

She comfortably won the first round of voting on Tuesday with 165 votes and has promised to "unite [the Conservative] party and the country" in the wake of the EU referendum.

Mrs May was followed by Andrea Leadsom with 66 votes, Michael Gove on 48 and Stephen Crabb on 34.

The former defence secretary Liam Fox was eliminated from the race after receiving only 16 votes from MPs.

Mr Crabb later withdrew from the leadership contest and both he and Dr Fox announced their support for Ms May.

In addition to his comments about Ms May, Mr Clarke was also heard telling former colleague Sir Malcolm Rifkind that Michael Gove was so right-wing he would likely start wars with “at least three countries” and that he did not really think Andrea Leadsom wanted to leave the EU.