Sir Elton John and David Walliams flashed their bums at Simon Cowell yesterday (08.08.12).

The music mogul got a full view of the 'Rocket Man' hitmaker and the comedian's bare behinds in St Tropez when each party's boats passed each other on the French Riviera.

David - who was with his wife Lara Stone on holiday - shouted across to Simon: ''I've got something for you.''

He then exposed his backside followed by the 65-year-old singer, and the 40-year-old TV star blew a kiss to the 'x factor' boss and shouted back: ''Love you Simon.''

David later took to his twitter account to reveal the pair had shown their butts to his 'Britain's Got Talent' co-star.

He wrote: ''I just mooned Simon Cowell. From a boat. That is true.

''And then someone a million times more well known than me mooned Simon Cowell too.''

David and Simon have also been having fun with a mystery dog this week, and the comedian posted a picture on his twitter account of the pooch climbing on the music mogul's face.

In a message accompanying the image, he wrote: ''A dog sitting on Simon Cowell's face.''

Elton has been spending time with his husband David Furnish and their 19-month-old son Zachary, as well as their friends, actor Neil Patrick Harris and his partner David Burtka and their 21-month-old twins Gideon and Harper, in St Tropez this week.