POLL: Should there be a general election this year?

Labour have said it is "crucial" that the UK has a "democratically elected prime minister" at a time of economic and political instability.

However, Mrs May set her face against a snap election when she launched her campaign for the Tory leadership on June 30, saying: "There should be no general election until 2020."

And her backers, including Mr Grayling, stressed that Mrs May was a senior member in the Tory team which won a majority and a mandate at the 2015 general election.

But other parties are likely to remind her of Mr Cameron's demand for an immediate election in 2007 on the grounds that Tony Blair's successor Gordon Brown "doesn't have the mandate (and) wasn't elected as prime minister".

Liberal Democrat leader Tim Farron added to the calls for a poll, saying: "Just 13 months after the last election the Conservatives have plunged the UK into chaos.

"It is simply inconceivable that Theresa May should be crowned prime minister without even having won an election in her own party, let alone the country."

Mrs May and right-hand man George Osborne led the tributes to the Prime Minister as he bid farewell to his top team by chairing an "emotional" final Cabinet meeting.

Cabinet ministers spoke of a "sad day" but also Mr Cameron's determination to remain upbeat and continue to drive the one nation Conservative agenda as he prepared to hand power to Mrs May.

The new Tory leader posed for photos as she arrived at 10 Downing Street in her trademark kitten heels on the day before she moves into the famous address as the UK's second female PM.

Mrs May faces a breakneck period of activity appointing a new Cabinet after the expected nine-week leadership campaign was truncated to just a couple of days by Andrea Leadsom's withdrawal from the contest.

After presenting herself as the unity candidate, Mrs May is expected to offer plum posts to leading figures from both the Remain and Leave camps from the EU referendum, in which she backed continued membership but kept a low profile.

Mr Osborne looks unlikely to stay on as Chancellor after the new PM trashed parts of his economic legacy, and is widely tipped to become Foreign Secretary in a potential job swap with Philip Hammond, who has long coveted the role at the Treasury.

Senior Brexiteer Chris Grayling will be rewarded for his role running Mrs May's campaign, possibly replacing her as Home Secretary.

And it is thought that a prominent Leave campaigner could be given the job of overseeing negotiations for the UK's departure from the EU and making good on Mrs May's promise that "Brexit means Brexit".

Mrs Leadsom is expected to be offered a job in recognition of her raised profile from the referendum.

But big question marks were hanging over the future of Brexit standard-bearers Boris Johnson and Michael Gove, who were seen to have blotted their copy-books in the wake of the referendum result but moved quickly to endorse Mrs May when Mrs Leadsom pulled out.

Mrs May will take up office on Wednesday, after Mr Cameron answers MPs' questions in the House of Commons for the last time and goes to Buckingham Palace to offer his resignation to the Queen.