Rob Gauntlett had his 19th birthday at Base Camp on Wednesday

Rob Gauntlett, of Petworth, Sussex, and James Hooper, also 19, of Wellington, Somerset, hope to begin the summit climb on Friday.

The record is currently held by Jake Meyer, 21, of Tetbury, Gloucestershire, who managed the climb in June 2005.

The youngest person to reach the summit was 15-year-old Ming Kipa Sherpa, who completed the 29,035ft ascent in 2003.

The teenagers, who spent two years planning their epic trek, scaled the 6,850m peak of Ama Dablam in Nepal as part of their build-up to the attempt on Everest.

On Thursday, the pair said they would move to Advanced Base Camp on Friday, rest there for a day and then start to move upwards through North Col, Camp Two and Camp Three before reaching the summit on 17 May.

They said five Korean climbers had just reached the summit in an "opening weather window", and the pair were feeling fit and strong and making their final preparations, after celebrating Rob's birthday on Wednesday.

On Tuesday, Rob said: "I was hoping to become the youngest Briton at 18 to climb Mount Everest, but my birthday is in two days' time and it is looking as though I will probably be 19 because we are still waiting for the weather."

And James said: "We have been up to 7,300m and everything up there is so much slower because breathing is a lot harder.

"You just feel a lot more lethargic and it is amazing how tough it makes things."