Boris Johnson has insisted he will continue speaking his mind as prime minister if he wins the Tory crown, despite the controversy some of his comments have sparked.

Launching his bid for Downing Street, the former foreign secretary said “the plaster comes off the ceiling” sometimes due to his remarks, but voters wanted plain speaking from politicians.

Pressed on a raft of past controversial comments, including saying Muslim women wearing burkas “look like letter boxes”, Mr Johnson defended his way of talking.

The front runner for the Tory leadership said: “I want to make a general point about the way I do things and the language I use.

“Occasionally some plaster comes off the ceiling as a result of a phrase I may have used, or indeed the way that phrase has been wrenched out of context and interpreted by those who wish for reasons of their own to caricature my views.

“But I think it’s vital that we as politicians remember that one of the reasons that the public feels alienated now from us all as a breed, is because too often they feel that we are muffling and veiling our language, not speaking as we find, covering everything up in bureaucratic platitudes, when what they want to hear is what we genuinely think.”

Tory leadership race
Boris Johnson is seeking the Tory leadership (Stefan Rousseau/PA)

“And, if sometimes in the course of trying to get across what I genuinely think I use phrases, language, that have caused offence, then, of course I’m sorry for the offence that I have caused.

“But I will continue to speak as directly as I can.”

Mr Johnson has courted controversy in the past by describing Prime Minister Theresa May’s Brexit plan as a “suicide vest” wrapped around the country.

The former foreign secretary was reported to have said “f*** business” in relation to Brexit.

There was booing and angry complaints at the campaign launch press conference from some journalists when Mr Johnson refused to take more than six questions.

Shortly after Mr Johnson began speaking, heckling from the street outside the venue was audible in the room.

Cries of “Bollocks to Boris” and “No to Brexit” from a protester could be heard during Mr Johnson’s launch speech.