Robbie Williams gave his Twitter followers an unexpected treat after posting a photo of himself topless.

However, he posted a topless photo online yesterday (August 15) which looks like he's been spending a fair bit of time in the gym too.

He originally uploaded the photo a day earlier from the account for his clothing line Farrell, but later posted it from his personal profile, tweeting:

"Bugger, meant to sent this from RW not Farrell...since I've got no clothes on. RW."

Williams' band Take That meanwhile performed at the Olympic Games Closing Ceremony to a massive audience on Sunday (August 12), but the 'Angels' singer wasn't present at the event.