His goal, with team mate Sarah Neale, 33, is to raise £5,000 for Operation Smile, an organisation providing surgery for children with cleft lips and palates. They will also be raising money for the Skye Mountain Rescue Team and Kids Company.

He will cross the Andes, skirt Bolivia's corner of the Amazon jungle and the world's largest salt flats, and squelch across wetlands to reach Asuncion, Paraguay's capital city.

Launched by founders of the Mongol Rally, this is a brand new race using a vehicle called a mototaxi (a cross between a motorbike and a sofa, used for short city hops).

John said: "Crossing a continent in such an unsuitable vehicle will be challenging – we'll be breaking down, getting stuck in waist-high mud, coping with altitude sickness and language barriers – but that's what makes it a real adventure. What's important is that the money raised will make a real difference to these brilliant charities."

To sponsor opportunities John call 07590 064210.