Boris Johnson says he has no idea why Theresa May is a more popular choice than him to be the next Conservative party leader after she surged 12 points ahead in a party poll.

Support for the Home Secretary to take over from David Cameron has rocketed to 35% among Tory activists while the Mayor of London languishes on 23%.

Mrs May was three points behind Mr Johnson in the last monthly poll, carried out by the ConservativeHome website and reported by The Times, but leapt by 15% this time round.

The hike in support has been linked to the Home Secretary's uncompromising speech to the Police Federation that saw her take the service to task in the wake of a series of scandals and demand it carry out significant reforms.

On his regular Ask Boris phone-in show on LBC, Mr Johnson dismissed discussion about the party's next leader as a "completely meaningless abstract consideration".

Asked why Mrs May was more popular than him, Mr Johnson replied: "Search me, gov.

"It's very, very good that there are loads of Conservative politicians that are doing good stuff at the moment."

Mr Johnson insisted he was "very happy" to be "mired" at 23% because there was "no vacancy" at the top of the party.