Boris Johnson's father urges Tory leadership rule change
Boris Johnson's father has said Conservatives from outside the Commons should be allowed to stand for leadership of the party.
Stanley Johnson denied that he was calling for the change at the request of his son, the London mayor and ex-MP who has been tipped as a future leader.
He said the move was "hypothetical" since the party would win the 2015 election with David Cameron in charge.
But the call nonetheless fuelled speculation about his son's prospects.
Boris Johnson has said he plans to serve his full term in office as London Mayor, which is due to run out in 2016.
'Have a crack'
But there has been speculation that he might seek to return to the Commons to mount a leadership bid. There is no rule against serving both as an MP and as mayor.
He once admitted he would like to "have a crack" at being prime minister "'if the ball came loose from the back of a scrum".
Mr Johnson Sr, a politician and former EU official, told BBC Radio 4's Today programme: "As you know, the Conservatives firmly expect to win an overall majority at the next election.
"We firmly expect the leader to be in place then. It's a question of just getting some appropriate system.
"It doesn't seem to me to be reasonable in this day and age, you know, you have got plenty of candidates out there. Why should the candidates only be Members of Parliament?
"I'm really suggesting that there are other people who have been elected, there have for example been MEPs, you know these are a reasonable bunch of people - men and women.
"All I'm saying is there is a case for looking at the rules. You've got MEPs, you've got councillors, you've got other elected mayors, you've, by the way, got a group of Lords, elected Lords, they have an election.
"I am saying, surely the moment has come to have another look at the rules?"
Mr Johnson added: "I'm old enough to remember that Alec Douglas-Home was not a Member of Parliament when he became the leader of the Conservatives."
Asked later in a BBC London interview whether his son would make a good prime minister, Mr Johnson replied "heaven knows" but said his experience as Mayor of London would "stand him in good stead".
"This is a job you grow into. You could say 'isn't he going to be a bit old'...but I think maturity may count here. He will have done eight, maybe ten years as Mayor of London, and that could stand him in good stead."