Tory leadership hopeful Rory Stewart plans to spent part of Father's Day playing Lego with his four-year-old son - between preparing for the Channel 4 Leader Candidates' Debate.

In a rare light-hearted moment during the frenetic contest to find Theresa May's successor, the Penrith & the Border MP told Good Morning Britain there are two people who are uninpressed by his efforts - his two children, aged two and four.

Asked how he will spend Father's Day on Sunday, Mr Stewart said: "I'm going to have to try to take some time out. But of course Sunday is the big debates, when I hope I'm up against Boris.

"I'm going to have to balance doing some Lego, which is what my four-year-old really wants, running around with my two-year-old, and finding a bit of time to prepare for this debate...

"My two year old and my four year old are slightly unamused by the amount of time I'm spending not playing with them."

He went on to say that his four-year-old had wanted to ask him a question at his leadership launch and was "really upset" when he refused to take a question he had, was: "Daddy, can we please play Lego with me when we get home?"

The MP was speaking as Heath Secretary Matt Hancock pulled out of the leadership race. 

In an interview on the BBC Radio 4 Today programme, Mr Stewart insisted that Boris Johnson should take part on the Sunday Channel 4 debate, saying: "It's incredibly important because he is by far the front-runner in this race.

"He's going to be the person in the final two and the real judgement members of Parliament have to make is who do they want going up against Boris in the final two.

"There's only one way they can judge that: by seeing Boris on stage against the other candidates."

Mr Stewart said it felt as though Boris Johnson appears to feel he is doing well but did not to want to risk which could upset his campaign but he was a great public performer and people needed to see and hear him.

He added: "It's really important for the legitimacy of the Prime Minister that this doesn't take place in a smoke-filled room but that the public is able see the candidates out in public..

"It's a lesson from the last leadership race that we need to test the candidates on television, in front of the public, with rigorous questioning before they become Prime Minister."

The MP called for clarity on whether the new PM would meet the Chancellors fiscal rules and we needed Johnson to get into the detail of how he would achieve a no-deal Brexit, and he added: "It can't just be a blind act of faith."

Mr Stewart got through the first round of voting, winning support from 19 fellow MPs - two more than required. In the next round he needs to garner the support of at least 33 MPs to stay in the race. Boris Johnson was supported by 114 MPs, making him the clear winner, but commentators say Mr Stewart's campaign has rapidly gained momentum.