Theresa May’s Conservatives have extended their lead over Labour to 16-points in a new opinion poll, prompting fresh speculation the new Prime Minister may call an early general election.

On current parliamentary boundaries, the latest of four survey’s reflecting the premier’s honeymoon period would increase the party’s slender majority of 12 to a massive 102.

Some 44 Labour MPs would lose their seats if the new ICM poll were borne out, leaving the party with only 188 MPs.

For now, such figures are fantasy politics, and considered unlikely to change the Prime Minister’s statement that she will not seek an election before the one due in 2020.

A snap election this autumn would add to the uncertainty caused by last month’s vote for Brexit, putting at risk the stability that Ms May’s swift election as Tory leader brought.

But some Tory MPs are starting to wonder whether Ms May would think again if her party’s poll lead continues into next spring. “She might find it hard to resist the temptation,” one senior Tory said. “She could argue that she needed her own mandate from the voters.”

The 6 most important issues Theresa May needs to address Show all 6 1 /6 The 6 most important issues Theresa May needs to address The 6 most important issues Theresa May needs to address Brexit The big one. Theresa May has spoken publicly three times since declaring her intent to stand in the Tory Leadership race, and each time she has said, ‘Brexit means Brexit.’ It sounds resolute, but it is helpful to her that Brexit is a made up word with no real meaning. She has said there will be ‘no second referendum’ and no re-entry in to the EU via the back door. But she, like the Leave campaign of which she was not a member, has pointedly not said with any precision what she thinks Brexit means Reuters The 6 most important issues Theresa May needs to address General election This is very much one to keep off the to do list. She said last week there would be ‘no general election’ at this time of great instability. But there have already been calls for one from opposition parties. The Fixed Term Parliaments Act of 2010 makes it far more difficult to call a snap general election, a difficulty she will be in no rush to overcome. In the event of a victory for Leadsom, who was not popular with her own parliamentary colleagues, an election might have been required, but May has the overwhelming backing of the parliamentary party Getty The 6 most important issues Theresa May needs to address HS2 Macbeth has been quoted far too much in recent weeks, but it will be up to May to decide whether, with regard to the new high speed train link between London, Birmingham, the East Midlands and the north, ‘returning were as tedious as go o’er.’ Billions have already been spent. But the £55bn it will cost, at a bare minimum, must now be considered against the grim reality of significantly diminished public finances in the short to medium term at least. It is not scheduled to be completed until 2033, by which point it is not completely unreasonable to imagine a massive, driverless car-led transport revolution having rendered it redundant EPA The 6 most important issues Theresa May needs to address Heathrow expansion Or indeed Gatwick expansion. Or Boris Island, though that option is seems as finished as the man himself. The decision on where to expand aviation capacity in the south east has been delayed to the point of becoming a national embarrassment. A final decision was due in autumn. Whatever is decided, there will be vast opprobrium PA The 6 most important issues Theresa May needs to address Trident renewal David Cameron indicated two days ago that there will be a Commons vote on renewing Britain’s nuclear deterrent on July 18th, by which point we now know, Ms May will be Prime Minister. The Labour Party is, to put it mildly, divided on the issue. This will be an early opportunity to maximise their embarrassment, and return to Tory business as usual EPA The 6 most important issues Theresa May needs to address Scottish Independence Nicola Sturgeon and the SNP are in no doubt that the Brexit vote provides the opportunity for a second independence referendum, in which they can emerge victorious. The Scottish Parliament at Holyrood has the authority to call a second referendum, but Ms May and the British Parliament are by no means automatically compelled to accept the result. She could argue it was settled in 2014 AFP/Getty

Tory MPs believe the temptation would be greater if Jeremy Corbyn is re-elected Labour leader in September because they are convinced Ms May would defeat him in an election. Labour is unlikely to unite behind Mr Corbyn; a continuing Labour civil war would be another attraction of an early election for the Tories. A bigger Commons majority would mean that Ms May was no longer at the mercy of a hard core of about 30 Tory Eurosceptics, who are already worried that she wants a “Brexite-lite” deal with the EU and are demanding a “hard Brexit.”

But allies of Ms May insist she will resist temptation. They say that she does not need a mandate because she was in the top team when the Conservatives won last year’s election and is now implementing their manifesto. Privately, they say there is no appetite for an election among Tory MPs.

Ms May is seen as a cautious politician and so may judge that the risks of an early election outweigh the benefits. She will be reluctant to go back on her own words, which could alienate some voters.

She knows that the three other prime ministers who took over in mid-term in the last 50 years – James Callaghan (1976), John Major (1990) and Gordon Brown (2007) – also enjoyed a poll bounce which took their party from a deficit to a lead over its main rival. Only one of them, Sir John Major, went on to win the next election, although Mr Brown might well have done if he had not dropped plans for an early poll after succeeding Tony Blair.

Another reason for caution is that the Brexit vote is having a chilling effect on the economy, which could go into recession, which is hardly a good time to seek a mandate when you do not need to. The case for holding on until 2020 is strengthened by the new constituency boundaries that take effect then, and will be worth about 20 seats to the Tories.

Sir John Major is the only person to take over as Prime Minister mid-term and win the next election in the last 50 years (Getty Images)

Calling an earlier election would also involve a risk because the Fixed Term Parliaments Act says that an election is held every five years. A poll can take place earlier if two thirds of MPs agree, which would mean that both Tory and Labour MPs supporting the move, or if Tory MPs voted for a motion of no confidence in their own government. Such votes could be messy, and could even go wrong – for example, if Mr Corbyn’s Labour critics did not back an election for fear of losing their seats.

The ICM survey put the Tories on 43 per cent, Labour on 27 per cent - its lowest rating with ICM since 2009 - Ukip on 13 and the Liberal Democrats on eight. Martin Boon, ICM’s director, said: “Clearly, the relative calm associated with the handover of power from David Cameron to Theresa May, allied to the current Labour leadership challenge, weighs heavily on electors’ minds.”