The former foreign secretary used a campaign video to drive home the message that leaving the EU with or without a deal on 31 October would bring Tory supporters back to the party if a snap general election is triggered. Mr Johnson also promised to both cut taxes and increase spending on schools and the police, and boost the use of stop and search powers in England.
His leadership launch came as Cabinet minister James Brokenshire called for outsiders in the leadership contest to stand aside.
Mr Brokenshire warned the party did not have “the luxury of weeks of navel-gazing” as the current 13-strong field is whittled down to a final two.
Mr Johnson’s campaign launch was clearly aimed at showing Tory MPs that he is the candidate most likely to secure them a general election victory, with carefully chosen footage of the former mayor of London on voters’ doorsteps.
On Brexit, he said: “If I get in, we’ll come out, deal or no deal, on 31 October.”
As well as extra funding for schools, Mr Johnson said “we need more police out there”.
He suggested he could “cut some taxes and you get more money in” to pay for his campaign pledges.
“If there is one message in that referendum of 2016, it is that too many people feel left behind, that they are not able to take part fully in the opportunities and success of our country,” Mr Johnson said.
“That’s why now is the time to unite our society and unite our country. To build the infrastructure, to invest in education, to improve our environment and support our fantastic NHS.
“To lift everyone in our country – and of course, also, to make sure that we support our wealth creators and the businesses that make that investment possible. Now is the time for us to believe in ourselves and what we can do.”
The number of MPs vying to replace Mrs May reached 13 on Sunday, with former minister Sam Gyimah throwing his hat in the ring.
Mr Johnson is the favourite among Conservative Party members, who will decide the next prime minister once MPs reduce the field to two.
His opposition to Theresa May’s Brexit deal and support for no-deal could be an obstacle to Mr Johnson securing enough support from MPs, but new pledges yesterday took his tally of endorsements to 36, giving him a double digit lead over Michael Gove.
A meeting of the backbench 1922 Committee today is not expected to follow through on a threat to raise the threshold for nominations, which currently only requires signatures from two MPs by the deadline of 10 June to enter the race.
However, one Tory MP told The Scotsman they expect the 1922 to change party rules so that multiple rounds of ballots take place on the same day, speeding up the process.