Nigel Farage says he wants to see the Conservative manifesto before deciding whether to vote for Boris Johnson’s party on December 12.
The Brexit Party leader this week stood down candidates in all 317 constituencies won by the Tories in 2017, including his own in Kent.
The decision means supporters living in almost half the UK’s seats will not be able to vote for a Brexit Party candidate on polling day.
Speaking to the PA news agency on the campaign trail in Ilford on Wednesday, Mr Farage said he wanted to ensure the changes indicated by the Prime Minister on Brexit were written into the manifesto before offering his own vote to the Tories.
If the changes – including refusing to extend the trade talks with the European Union past 2020 and ruling out future political alignment with Brussels – do not appear, then the MEP has threatened to vote down the Withdrawal Agreement in the European Parliament.
Asked whether he could vote Tory personally in his own constituency, Mr Farage said: “I want to see the manifesto. Let me see what is in the manifesto.
“I’m hoping and believing that what Boris said last Sunday is going to be in the manifesto.
“If that is in the manifesto then the deal as was is about to be changed in quite a big way.”
The former Ukip leader said he would “never have voted for” the PM’s original Brexit deal, which he called “terrible”.
London MEP Ben Habib, in a warm-up speech to the Essex crowd at Gator ABC boxing club, labelled the PM’s exit terms “awful” and akin to surrender.
Mr Farage added: “The original deal I would never have voted for – don’t forget, I’m still an MEP.
“It would come back to the European Parliament, I would never have voted for it in a month of Sundays.
“We get those changes and we start to get towards Brexit and it is very different.”
Questioned on whether he could back the deal in Brussels following his “unilateral” pact with the Tories, Mr Farage added: “Not as it is, absolutely not. But with the changes Boris has indicated, yes.”
The anti-EU figure assured backers that he would not be standing any further candidates down and vowed to take on every Labour and Remain-backing MP in the country.
“We’re going to stand against every single one of them,” he told them from the centre of the boxing ring.
Mr Farage, who appeared alongside heavyweight boxer Dereck Chisora at the event, said he found it “incredible” that Mr Johnson had not reciprocated in taking Tories off the ballot papers in Labour marginals where the Brexit Party are the main challengers.
“There is risk now of the leave vote being split. It is them now putting this at risk, not me,” he said.
“The Conservatives have refused to give anything. There is, I can assure you, quite widespread disenchantment among leave voters of all persuasions that my gesture has received no reciprocation at all.”
He dismissed talk of offering a reprieve to the Brexit-backing Labour MPs who voted for the deal at second reading in Parliament last month.
“We are doing it on the parties’ national pitch,” he said.
“If you start to do individual seats then you start to get a very confused picture and it is hard to explain what you are doing.
“We know the Conservative Party are standing on this manifesto.
“We don’t like the deal – we’d like to propose changes to it.
“We know our position there.
“We know Labour want a second referendum and anybody standing for the Labour Party is doing it on that ticket.”