Boris Johnson promises to boost police numbers by 20,000 in £1.1bn move if he becomes prime minister

Boris Johnson has pledged to boost police officer numbers if he wins the Tory leadership contest and becomes prime minister (Picture: AFP/Getty Images)

Boris Johnson has pledged to boost police numbers by as many as 20,000 within three years if he becomes prime minister.

The Tory leadership favourite said he would expand the service to more than 140,000 officers by mid-2022 if he wins the race for Number 10.

Former London mayor Mr Johnson said the £1.1 billion move would focus on rural areas that have seen the biggest funding reductions.

He said the funds would come from the £26 billion "headroom" reserves set aside by Chancellor Philip Hammond.

Conservative MP and leadership contender Boris Johnson during his visit to the Thames Valley Police Training Centre in Reading (AFP/Getty Images)

It came as Mr Johnson faced another hustings appearance with rival Jeremy Hunt on Thursday.

Mr Johnson, who visited the Thames Valley Police training centre near Reading, Berkshire, on Wednesday, said: "What we are saying is that we are going to use some of the existing headroom, quite a small amount, about £1.1 billion, to put more police officers out on the street and I think that is what the public want."

Boris Johnson visits the Thames Valley Police Training Centre (AP)

Pressed on whether he had already pledged the headroom funds for other initiatives, Mr Johnson said: "On the contrary, we have been positively frugal by comparison with a certain other campaign that I could mention.

"We are still well within the £26 billion that the Chancellor squirrelled away quite prudently, the money is going on education, a little bit on broadband - and that is already allocated - and on policing as well."

Mr Hammond has publicly warned Mr Johnson and his rival for Downing Street, Foreign Secretary Jeremy Hunt, that a no-deal Brexit would mean the reserve funding would need to be used to deal with the aftermath of withdrawal, and would not be available for spending pledges.

Both Mr Johnson and Mr Hunt have said they would be prepared to exit the EU without a deal on October 31 if they could not get an improved agreement with Brussels.

Mr Johnson’s visit to Thames Valley Police Training Centre was made as a clear majority of Tory police and crime commissioners around the country backed him to become prime minister.

Eleven commissioners signed a letter hailing his “outstanding work” as mayor in tackling violence.

“We need a prime minister who has a proven record of reducing crime and who will back police with the power and resources they need,” said the group.