Although the interview, on Granada's 'Tonight with Trevor McDonald' on ITV1, is set to focus on his preparation for the forthcoming London Marathon, an ITN spokesman confirmed that Campbell would also respond to questions about the Government's bid to win public support for possible military action in Iraq.
Tonight's executive producer Jeff Anderson added: 'The Blair government is doing its utmost to win hearts and minds over its stance on Iraq and Mr Campbell is at the forefront of that campaign.
'It's probably the biggest challenge he's ever faced in Downing Street and viewers will be able to see how he's coping with it.'
Campbell is taking part in the marathon in April to raise money for the Leukaemia Research Fund in tribute to his close friend, journalist John Merritt, who died from the disease 10 years ago.
In the programme, ITN political correspondent Lauren Taylor will be following Campbell both at work and at home during his training for the marathon attempt.
Campbell's 'Tonight' appearance follows an interview in The Observer in January, also to gain publicity for his London Marathon attempt. So far he has raised more than £82,000 in sponsorship pledges.
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