RISHI Sunak has branded a shock poll showing Reform overtaking the Tories as "a blank cheque" for Labour and admitted it would hand Sir Keir Starmer the keys to No10.
The YouGov survey that showed Nigel Farage's party on 19 points to the Conservatives' 18 has upended the PM's visit to Italy for the G7.
But the PM attempted to put a brave face on the poll that has left Tory MPs reeling.
He insisted: "We are only halfway through, right? So I am fighting very hard for every vote."
Quizzed over breakfast by the press pack in Puglia on the fringes of the summit, Mr Sunak said: "If this poll was replicated it would hand a blank cheque to Labour.
"It would be handing Labour a blank cheque to tax everyone... to tax their home, their pension, their car, their family and I’ll be fighting very hard to make sure that doesn’t happen.
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He added: "Ultimately a vote for anyone who is not a Conservative candidate makes it more like that Keir Starmer is in No10."
Attempting to turn the blow on his right flank into an attack on Labour, he added: "When people are thinking about the substance of what they want to see in a future government.
"If you want to see control over borders? You’re going to get that from us.
"You’re not going to get that from Labour.
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"They are going to cancel the Rwanda scheme, they’re not going to put a cap in place on legal migration
"If you want a sensible approach to Net Zero, I’ve already announced that. Labour will reverse it."
"We are the only ones offering the triple lock plus".
Urging wavering voters to think again, he said: "I think that people can see very clearly now the choice between two parties and that will crystallise for people between now and polling day.
"We are only halfway through, right?"
He later added there would be a “massive difference on tax” with the Labour manifesto.
ANALYSIS: Stuff of nightmares

By Ryan Sabey, Deputy Political Editor
Labour winning a 'super majority' at the election is giving the Tory party nightmares.
Sir Keir Starmer could be heading back to the Commons with a majority of 416 seats if one weekend poll is to be believed.
Defence Secretary Grant Shapps says he fears there could a real lack of accountability from other parties if they are destroyed.
The Tories have described this as a "blank cheque" approach which would allow Labour to pass whatever legislation they want.
Polling has shown the Tories could win less than 100 seats and this could mean they won't be an effective opposition.
There could literally not be enough people to fill all the shadow positions for the next Tory leader.
Miriam Cates says Labour may even create "constitutional vandalism" by being given such a majority.
She fears a new Labour government would take even more power out of the hands of Westminster and giving it to technocrats and the civil service if given the chance.
The talk of a super majority also speaks to another predicament the Tories find themselves in.
Concern is growing within Tory circles that they will receive an almighty hiding from the electorate on July 4.
Look at how the language has changed in recent weeks.
Rishi Sunak told The Sun at the start of the campaign that he was eyeing up an election win and England would win the Euros.
That now seems like a pipedream.
Defence Secretary Grant Shapps has been touring the TV and radio stations this morning telling voters not to hand Sir Keir Starmer a "blank cheque".
He told the public that Labour shouldn't be given "unchecked" power especially when their plans are vague.
He put on a brave face telling Times Radio saying there was still "everything to fight for".
The seats both parties have been visiting tell their own story.
On Monday, I visited Horsham in West Sussex, which has a 21,000 Tory majority.
Sir Keir Starmer has visited Monmouthshire which features way down the list of Labour target seats.
For Labour are on the attack and for the Tories it appears to be a damage limitation exercise.