A teenager from Sussex has become the youngest Briton to climb the world's highest mountain.

Rob Gauntlett celebrated his 19th birthday at Mount Everest's base camp less than a month ago along with his friend James Hooper.

The gap year students, who were pupils at Christ's Hospital, near Horsham, tackled the 29,035ft mountain from the north and reached the summit at 3.15am yesterday.

During their ascent Rob, from Petworth, and James, from Wellington, Somerset, struggled with illness and weight loss.

Their triumph means Rob is the youngest Briton to scale Everest as he is three weeks younger than James.

Speaking from the summit, Rob said: "It's incredible up here looking out knowing nowhere in the world is higher than you.

"James and I are keen on getting the message across to young people to follow your dreams. This has been our dream for three years. Get out there and make it happen."

They reached the peak after a ten-hour trek through the night from the last camp.

Rob's mother Nicky said her son was motivated to climb Everest to raise £1 million for Cancer Research UK after his aunt, Joanna Browne, 40, was given two years to live with cancer of the oesophagus. His grandmother Rosemary Lee also died of cancer nine years ago.

Nicky said the family, including Rob's father David, sister Louise, 22, and brother Tim, 16, had no sleep on Tuesday night as they waited for a phone call to say Rob and James had reached the summit.

Mrs Gauntlett said: "We were all desperately nervous. We have been extremely worried. The most amazing thing has been being able to talk to him via satellite phone. We are all very, very proud."

She said the family would wait until Rob and James reached camps further down Everest and were off oxygen before they started celebrating.

Rob, who weighed ten-and-ahalf stone, lost three stone and became dangerously thin. Last autumn the pair successfully tackled the challenging 22,400ft peak of Ama Dablam in Nepal as part of their build-up to the attempt on Everest.

They are due to reach base camp by Friday evening and were to fly home on June 7 but now hope to leave earlier.

The previous youngest Briton to climb Everest was Jake Meyer who was 21 when he reached the summit in June 2005.

Rhys Jones, who was climbing the opposite face of Everest at the same time as James and Rob, reached the summit a few hours later on his 20th birthday.

He is now the youngest person to reach the peak of the highest mountain on each of the world's seven continents.

For more information or to make a donation, visit www.everest-2006.com