Little Britain star fundraising for Sport Relief

David Walliams has started his 8-day swim along the length of the River Thames to raise money for Sport Relief.

The comedian is following up his 2006 English Channel fundraiser by undertaking the 140-mile long challenge and was cheered on by supporters as he left Lechlade, Gloucestershire, on Monday.

‘I think about happy things,’ says David, 40.

‘I think about what I’m going to eat when I get out.’

David planned to complete his marathon in trunks but was forced to stop and don a wetsuit because his back began to turn blue, a sign of hypothermia.

‘I’m a bit daunted by the way this has started,’ the Little Britain star told the Daily Mirror.

David will faces freezing temperatures, strong currents and the risk of disease as he swims towards London.

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Anna Francis