Iain Duncan Smith: Remembering the time former Work and Pensions Secretary clashed with James O'Brien

The pair had a heated exchange over the Government's Work Programme

Liam O'Brien has a knack for unsettling politicians (LBC Facebook)

Politicians are notoriously unflappable – or at least, they like to think they are – often avoiding questions or traps in debates and interviews by repeating the same rehearsed rhetoric.

But there is one interviewer who has proved his ability time and time again to upset politicians and disturb their composed demeanour by posing provocative and difficult questions they struggle to answer.

James O’ Brien famously had his interview with Nigel Farage brought to an abrupt end after reducing the otherwise self-possessed Ukip leader into a spluttering, furious mess.

O’Brien also had his day with Iain Duncan Smith on 20 February 2013 when the pair had an “explosive bust-up” over the Government’s welfare to work programme, which critics said forced people to work for free or face losing their benefits.

The former Work and Pensions Secretary, who resigned on Friday over cuts to benefits for disabled claimants, appeared on LBC to discuss figures showing a fall in unemployment levels. But O’Brien and Mr Duncan Smith quickly clashed after the presenter questioned a scheme where those involved worked without payment.

"If you just want to make a mess of this, that's fine," snapped Mr Duncan Smith at one point during their exchange. "That's your prerogative," O' Brien responded. Listen to the full exchange above.