Nigel Farage has been accused of sounding “conspiracy theory-like” by the BBC’s political editor in a tense exchange.

The Reform UK leader clashed with Chris Mason during his first sit-down interview since winning back his seat in the Clacton by-election last month.

Farage triggered the contest by resigning after a parliamentary standards probe was launched into his failure to declare a £5 million gift he received from a Thailand-based crypto billionaire.

Farage insisted he has not broken any rules, claiming “it was not a political donation” and pointing out that he was not even an MP when he received it in 2024.

Although the Reform boss increased his majority, his main challenger was Count Binface because Labour, the Tories, Lib Dems and Greens all refused to take part.

Now Farage back in the Commons, the parliamentary investigation into the donation has resumed.

If he is found to have broken the rules and is suspended by parliament’s standards committee for more than 10 days, yet another by-election could take place.

When Mason asked what “on earth was the point” of last month’s by-election, Farage insisted the committee – which is made up of Tory, Labour and Lib Dem MPs plus seven members of the public – would not give him a fair hearing.

Asked about the a separate Metropolitan Police investigation into four large donations to Reform UK, Farage insisted “we live in a complainant society”.

He said: “If you complain about me, automatically that triggers an investigation. So we’re under investigation every day for virtually everything we do, because the other political parties are constantly writing to all the authorities.

“There is a whole ecosystem with a century of development around this, and we come along from virtually nowhere and threaten the whole thing.

“So I think what you’re seeing is the establishment, in a very coordinated way, fighting back. But do you know something, it isn’t going to work.”

Mason replied: “Doesn’t that sound a bit conspiracy theory-like? This ‘the whole world’s out to get us’ stuff.”

Farage insisted there was a “degree of collusion” between Reform’s opponents, who he claimed have been working to “attack” his party since its success in May’s local elections.

He added: “It’ll keep coming. This won’t stop. Every single thing we do will be questioned in all sorts of ways. This will not stop. They will continually try and do this to us.”

Asked who “they” are, Farage said: “People who, people who hold positions of power, influence, and money don’t want new kids on the block succeeding.

“It’s the whole ecosystem.”

He then suggested he and Donald Trump had “sat and talked” about the people who allegedly work against them, before changing his mind and adding: “I haven’t actually discussed this with him.

“But I can see the similarities because again, he was an outsider, he wasn’t part of the system.”

When Mason put it to Farage that scrutiny was “inevitable” considering he is angling to one day be prime minister, the Reform leader replied: “There’s been a wilful attempt, and it’s gone on now for months, to say that everything to do with Reform, that every individual involved with Reform is somehow a crook.

“That’s been the attempt that’s been made.”

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