The mutual love-in between U2 and Coldplay is well established at this point, but it came to the fore once again during an episode of 'Jimmy Kimmel Live' that aired yesterday.

Bono and Chris Martin joined forces for a special edition of the show for AIDS charity [RED], where they collaborated on 'One for My Baby (and One More for the Road)’ - a song first sang by Fred Astaire in the 1940s and later popularised by Frank Sinatra.

What's more, even Sean Penn makes a cameo as a bartender in the stylised video, as Martin plays piano and Bono croons his little heart out.

Watch it below: