Steven Woolfe is reviving his bid to become Ukip leader after the 18-day reign of Diane James ended, but said he recently had discussions about defecting to the Tories.
The Ukip MEP was blocked from running in the previous contest to succeed Nigel Farage – for which he was the favourite – after submitting his forms 17 minutes late.
He announced on Wednesday that he was reigniting his leadership ambitions, after James quit because she felt she did not have the support of MEPs and party officials.
However, it is understood senior Tories believed he might have been about to jump ship before the news emerged that James was unhappy in the job.
One Tory source said some conversations had taken place between senior party figures and Woolfe about the possibility of him joining the party. A source in Woolfe’s camp confirmed this and said he had thought about it “very, very seriously”.
In a statement, Woolfe said: “I have been enthused by the start to Theresa May’s premiership. Her support of new grammar schools, her words on social mobility and the growing evidence that she is committed to a clean Brexit prompted me, as it did many of my friends and colleagues, to wonder whether our future was within her new Conservative party.
“However, having watched the prime minister’s speech on Sunday, I came to the conclusion that only a strong Ukip can guarantee Brexit is delivered in full, and only our party can stand up for the communities of the Midlands and the north.”
He added: “We can replace Labour as the main opposition party. We can build on our remarkable achievements, stand up for the ignored working class and secure a radically different political landscape in Britain for a generation. Under my leadership, that is what we will do.”
The admission will give ammunition to other candidates likely to stand against him, who may argue that being too close to the Conservatives in ideology could harm Ukip’s attempt to win votes off Labour in the north of England.
It is understood Paul Nuttall, the former deputy leader who has a strong support base in the north of England, is considering whether to run.
Suzanne Evans, the former deputy chair who clashed with Farage, Peter Whittle, a London assembly member, and several former leadership candidates, including party organiser Lisa Duffy, could also run for the job. Raheem Kassam, the former chief of staff to Farage, is also expected to run.
Arron Banks, a major Ukip donor and ally of Farage, told the Guardian he would still be supporting Woolfe for the leadership, because it was natural to have considered the Conservatives after the way his previous bid was treated.
He said the committee was a “motley collection of amateurs” who would destroy Ukip. “Watching them try to run the modern political movement which Nigel built is like watching a team of circus clowns trying to carry out a pit stop at the Silverstone Grand Prix,” he said.
He said Woolfe was a “working class boy from the North, (who) is better positioned than anyone to help Ukip displace Labour as the party which stands up for ordinary people, believes in Britain and fights for the national interest”.
In comparison, the other candidates who ran last time were “nothing but a rabble of no-name, no-talent nobodies... Who would be out of their depth in a paddling pool and couldn’t be more unfit to run a modern political party.”
It is understood Ukip has called an emergency national executive meeting to discuss the rules of the contest, which was triggered after James declined to formalise her leadership with the Electoral Commission. She signed her forms signalling it had been done unwillingly by writing “under duress” in Latin.
Amid turmoil in the party, Farage declared himself to be the interim leader of Ukip, given the job had not formally changed hands. He said he had spoken to the Electoral Commission, which confirmed he was technically still leader. He made the declaration amid rumours that Ukip’s ruling body could try to install Neil Hamilton, the former Tory politician and Ukip leader in Wales, as temporary leader.
Farage told BBC2’s Victoria Derbyshire show he hoped that “horror story” would not come to pass, saying Hamilton was not good for the image of the party.
James was elected at Ukip’s party conference last month. In a statement released on Tuesday night she explained her decision not to take up the post.
The statement said: “It has become clear I do not have sufficient authority, nor the full support of MEP colleagues and party officers, to implement the changes I believe are necessary and upon which I based my campaign.”
However, Farage claimed she had a “personal problem” relating to the health of a family member and had been shaken by being spat at while at Waterloo station. “As far as the party is concerned, it’s not a great day but it is not the end of the world,” he said.