Rishi Sunak has stuck by Boris Johnson as he officially launched his leadership bid, saying he won’t “demonise” his former boss.

The ex-chancellor defended the prime minister, calling him “one of the most remarkable people I have ever met”, despite resigning last week over Mr Johnson’s conduct in office.

Fellow contenders Tom Tugendhat and Kemi Badenoch carried out their own official launches at the same time – with Mr Tugendhat pledging to cut fuel duty by 10p and Ms Badenoch refusing to enter into a tax cut “bidding war” against the other candidates.

Politics Hub: Johnson loyalists to back ‘stop Rishi’ candidate

Addressing the issues around the PM in his speech, Mr Sunak said: “Did I disagree with him? Frequently. Is he flawed? Yes and so are the rest of us. Is it no longer working? Yes and that is why I resigned.

“[But] I will have no part in a history that seeks to demonise Boris.”

Asked by Sky News’ Beth Rigby if he accepted he was seen as “corrosive” by many Tory MPs after his support for Mr Johnson – and sudden withdrawal of it – as well as issues about his wife’s tax affairs, Mr Sunak insisted he had backing from “all wings of the party”.

He continued: “That’s why I believe I am best placed to bring the party back together, but also reunite the country, because ultimately, that’s the most important thing.”

The main thrust of his pitch, however, was a promise to “steer our country through these headwinds” of a tough economy, adding: “Once we have gripped inflation, I will get the tax burden down. It is a question of ‘when’, not ‘if’.”

Mr Sunak made his bid with the support of Deputy Prime Minister Dominic Raab and Transport Secretary Grant Shapps, who dropped out of the race moments before Mr Sunak’s launch event began.

Opening the event, Mr Raab said: “I know that Rishi has got what it takes… to provide the leadership that we need to steer the country through tough economic times.”

A total of 11 candidates had put themselves forward for the race, with one – Mr Shapps – now dropping out. However, announcing their intentions to run does not secure them a spot in the leadership election.

The window for candidates to get onto the ballot opens at 12pm, and they have until 6pm to secure the backing of at least 20 MPs to move forward to the first vote tomorrow.

Come Thursday, this threshold will rise to 30 MPs and keep rising until the party is left with just two candidates to put to its wider membership.

The winner of this final stage will then be revealed on 5 September.

Boris Johnson will remain in Number 10 acting as a caretaker prime minister after announcing his departure last week following a raft of resignations over his handling of disgraced MP Chris Pincher.

But Labour is attempting to oust the prime minister more quickly by calling a confidence vote in Parliament on Wednesday.

The ‘stop Rishi’ candidate?

Following this morning’s cabinet meeting in Number 10, both Brexit opportunities minister Jacob-Rees Mogg and Culture Secretary Nadine Dorries announced their backing for Liz Truss as the party’s next leader.

They described the foreign secretary as a “strong Brexiteer” and someone who had spoken out against tax rises.

Sky News’ political editor Beth Rigby said that by coming out for Ms Truss, the influential pair were signalling to the right of the party that she was “the stop Rishi candidate”.

Asked by reporters if that was the case, Mr Rees-Mogg did not deny it, merely replying: “She is the best candidate.”

Meanwhile senior backbencher David Davis gave his backing to former Defence Secretary Penny Mordaunt, who is leading the Conservative Home poll of party members on who they want as their next leader.

He told Beth Rigby: “We need high integrity – we can’t afford any more scandals after the last two years – [and] she is a woman of incredible integrity.”

Sky News is hosting a live TV debate with the contenders vying to be the next leader of the Conservative Party and therefore prime minister, and you could be in the virtual audience.

The debate will take place on Monday 18 July hosted by Sky News presenter Kay Burley.

If you would like to be a member of the virtual audience and be in with a chance of asking a question, please email NewsDebates@sky.uk.