Olympic champion Greg Whyte was "absolutely gutted" when his attempt to swim the Channel ended in fog and failure on Sunday.

Galvanised by Little Britain comedian David Walliams' successful  crossing last month, Greg had been determined to outdo his protégé's impressive time of 10 hours and 34 minutes. 

And he was well on his way to achieving his goal when the weather closed in.  A disappointed Greg said: "I was in the water for nine hours and 10 minutes and only two miles from the French cost. 

"But suddenly the weather changed - the fog came down and the waves went up.  I spent 2 1/2 hours going nowhere.  There was a very heavy tide pulling me south and there was no point in going on. 

"I was pulled out, exhausted and desperately disappointed, within sight of the coast." 

It had all started so well.  Greg, 38, was making good progress and was surprisingly unaffected by the cold, which had been his biggest fear. 

The former Luton school boy made the halfway point within four hours. 

But what had the makings of a record-breaking crossing ended within frustrating sight of victory.  And it's unlikely the seven times British modern pentathlon champion will try again.

"It's a matter of time and effort," he explained. 

"Only 10 per cent of those who attempt the crossing complete it, mainly due to weather." 

Greg, who heads the English Institute of Sport and has a PhD in n sports science, agreed to coach award-winning comic Walliams for his Channel challenge. 

the star turned in a stunning performance with a speed fast enough to earn him a place among the elite top 50 who have taken the plunge - and raised more than £1 million in sponsorship for comic Relief. 

The pair have become close friends since they started training together. 

Walliams accompanied Greg in the support boat and was on hand to commiserate, telling his bathing buddy no one could have finished under those conditions. 

Greg's upset on both the personal and professional fronts.  He was doing the swim for charity and feels he's let down his supporters.  but he's still raised more than £2,500 which will be split between Comic Relief and his favourite charity CRY (Cardiac Risk in the Young), of which he is chairman.

He and Walliams have already set their sights on Comic Relief 2008 and are planning a similar stunt.  Meanwhile, he's trying to be philosophical about his abortive attempt. 

"That's life," he shrugged.