Former marine completes day one of Antarctic ski

Sam Cox has begun his attempt to break the World Record for the longest solo unsupported crossing of Antarctica

A former Royal Marine has officially begun his world record-breaking attempt to ski unsupported, on his own, across Antarctica.

Sam Cox stepped onto the ice at Union Glacier on Sunday following a two-week delay in Chile after strong Antarctic winds prevented planes from landing.

On Monday, he crossed the official start line, before he skied the first 9.94 miles (16km) towards the pole.

He said: "Overall, I’m really pleased with the day and hopefully I can keep this pace for the next few weeks, especially when my pulk [supplies sled] gets lighter."

Mr Cox arrived in Antarctica on Sunday and set off from the start line on Monday

The wait for a weather window to land in Antarctica has now given Mr Cox just 78 days to complete the crossing.

The route was already expected to take 75 days, leaving a tight margin for error or bad weather.

“While I’ve been training for this for over two years, and know I’ve made all the preparations I can, I’m still attempting something very ambitious; so I’m not taking anything for granted,” Mr Cox added.

He is expected to cover more than 1,200 miles (2,000 km) of unforgiving Antarctic tundra, with ambition to break the existing world record by more than 310 miles (500 km).

Mr Cox's team said the route had never been attempted before and would be longer in distance than any solo unsupported Antarctic expedition in history.

Captain Preet Chandhi set the current world record for the longest solo unsupported crossing of Antarctica in January.

During the expedition, she covered 922 miles (1,485km) in 70 days and 16 hours, enduring difficult conditions.

His route will started at the coast of Berkner Island and will finish at the base of the Reedy glacier on the Ross ice shelf, via the South Pole.

Mr Cox's progress is being tracked by his team and family online.