Boris Johnson is loved by many ordinary members of the ruling Conservative party, who will have a vote.

Britain's Boris Johnson, the former foreign minister, ex-mayor of London and leading Brexit campaigner, confirmed Thursday he will run for the premiership when Theresa May quits, British media reported.

"Of course I'm going to go for it," he told a business event in Manchester, northwest England, confirming what most commentators and colleagues have long assumed.

Ms May has yet to set a date for her departure from Downing Street, but she has promised to step down once the first stage of Britain's exit from the European Union is secured.

Many of her ministers and senior lawmakers are already jockeying for position, holding photo opportunities and giving wide-ranging speeches that go well beyond their official briefs.

Mr Johnson, who was poised to run against Ms May when she took office after the 2016 referendum, has long been assumed to be a candidate when the right time comes, but has recently kept out the limelight.

Known abroad for his gaffes and accused of misleading voters over Brexit, he is nonetheless loved by many ordinary members of the ruling Conservative party, who will have a vote.

Johnson quit as foreign minister last year over the government's Brexit strategy and has been an outspoken critic of the divorce deal May struck with Brussels last November.

The deal has been rejected three times by the House of Commons, forcing May to delay Brexit twice - while also postponing her own departure.

She announced this week she would bring it back for a fourth and likely final time in the week beginning on June 3.

May hopes to secure parliament's approval for the deal by July, at which point she is expected to step down.

If the plan is rejected again next month, few expect her to hold on that long.