Alastair Campbell has hit out at “conmen” Boris Johnson and Nigel Farage as he told Brexit voters on BBC Question Time they were “lied to”.

The corporation’s flagship politics show on Thursday held a “special” in Clacton-on-Sea in Essex to mark the seventh anniversary of the 2016 vote. Some 70% of people in the area voted to get out of the bloc and only Brexit voters were in the audience for the programme.

Campbell, the Tony Blair-era Labour Party spin chief, has been a fierce critic of leaving the European Union. On the show, the Rest is Politics podcaster said he understood why the audience members wanted to exit the EU – but that they were “lied to” and told it “would be pain-free” and “all be upsides”, as he pointed to the fall in the pound, a lack of a trade deal with the US and the claim of more money for the NHS.

He said: “Look, I understand why a lot of you guys voted for Brexit because you felt that Johnson, Farage … these conmen were coming along offering you something that was going to make your lives better.

“And I was in a school today, just a few minutes away from here. Clacton Coastal Academy. Really bright kids. Really nice teachers. Fantastic school in a very tough area, and I asked the kids what they thought of Brexit and all but two said they would vote to rejoin the European Union if they had the chance.”

He went on: “I don’t blame you for voting. I blame them for lying to you. They lied. They’ve not been properly held to account.

“Johnson’s gone from lying about Covid. He’s still not properly been held accountable for Brexit.

“And we’re all of us paying a higher price in our cost of living and everything else because of the lies that we were told.”

He later said Brexit is “one of the biggest acts of self-harm that we as a country have ever inflicted upon ourselves”, and that Johnson “never believed in Brexit”.

“Boris Johnson went for the referendum as a way of advancing his own career and becoming prime minister,” Campbell said. “The mess he’s left this country in, he should never be forgiven.”

Critics of leaving the EU have cited the impact on the pound, imports and labour costs, and other economies on the continent powering ahead. Britain’s higher rate of inflation compared to other major economies has also been blamed in part on Brexit thanks to higher administration costs and a small pool of workers.