A rescue team found the bodies of Rob Gauntlett, 21, and another British climber high on Mont Blanc de Tacul near Chamonix, The Sunday Times reported. Gauntlett's mother, Nicola Gauntlett, told the newspaper the two friends were ice-climbing.
"At the moment we don't know exactly what happened but there was obviously a big fall and they both died," she said. "We've only just been told the news."
Gauntlett and James Hooper, who was also 19 at the time, climbed Everest in 2006. The friends later traveled from the geomagnetic South Pole to its northern counterpart under their own power, something no other explorer had done.
Authorities in France had not released the name of the other climber killed with Gauntlett but said it was not Hooper. A police spokesman said four people have been killed in ice falls in the region this season.
Gauntlett began his career of adventure at age 15 when he traveled from Lands End to John O'Groats, the traditional extreme points of Britain, by bicycle.