The return of Boris? PM wants his ‘best striker’ back in parliament

David Cameron has unexpectedly given his blessing for Boris Johnson's Commons return – putting pressure on the mayor of London for a decisive answer one way or the other.

Johnson has strenuously avoided openly admitting whether he intends to make a last-minute bid to get re-elected to parliament – paving the way for a potential leadership challenge – in next year's general election.

Cameron has until now avoided intense speculation about Johnson as a possible successor to the Conservative party leadership.

But he has now accepted his Oxford contemporary has ambitions to get into No 10, admitting that "there is nothing ignoble about wanting my job".

Speaking in a Sun interview with the actor and comedian James Corden, Cameron said of Boris: "I want him to get back in Parliament. I think he's great.

"It's a bit like football – if you have got a great striker you want him on the pitch.

"It's up to him. He can complete as mayor, or he can stay on as mayor and come back to the House. I want him on the team."

Allies of chancellor George Osborne had presented the possibility of Boris' return as part of a plot to oust Cameron at some stage in the next parliament.

Earlier this week Boris' father Stanley Johnson called for a change in the Tory party leadership rules to allow the party to be led by a politician who is not a member of parliament.

Now Cameron seems to have accepted he faces other ambitious figures within the Tory party.

"It wouldn't be a great job to have if people didn't want it," he added.

"There is nothing ignoble about wanting my job."

Cameron said he thought Johnson "did brilliantly over the Olympics".

"He has an amazing capacity to defy gravity that other politicians don't. And also he is fun. I find him genuinely amusing."

Finding a seat for Johnson in parliament may prove difficult at this late stage.

He would be obliged to face scrutiny from the party at an assessment weekend – and find a sitting Tory MP willing to give up his or her seat.

Earlier this month Johnson himself said of the leadership question: "I am so sick of this subject, I think I'm going to expire sometimes. I am going to get on with my job as mayor of London."