Robbie Williams has gone viral on social media after he found himself at the centre of a live TV gaffe during the broadcast of the World Cup final on Monday.

The British singer was discussing the game during a live broadcast when an unidentified white substance appeared to fall from his mouth onto the microphone he was holding.

He notices it, and proceeds to pick it off the microphone. But then, in an attempt to flick the thing away, Williams inadvertently ends up placing it on the side of his forehead where it awkwardly remains for the rest of the interview.

Pop icon's gross moment on live TV

The singer has since addressed the incident in a cheeky social media video, in which he confirmed the object was a mint.

“I’d just like to apologise for the object that fell onto the microphone yesterday, it was deeply unprofessional,” he said in the Instagram video, while lying in bed shirtless.

Robbie Williams speaks out on World Cup gaffe

“And people worried about me, but, it’s OK because I had several more,” he laughed before sticking out his tongue to reveal two mints.

He also captioned the video, “Just woke up and feeling…. Mint x.”

Before Williams’ confirmation, While social media was awash with theories and claims of what the substance could be that he accidentally spat out while passionately discussing the football match between Spain and Argentina.

“Looks to be a bit of food or possibly spittle coming out of his mouth,” insisted one viewer.

“It came out of his mouth and could easily be a tonsil stone,” remarked another.

While a third insisted: “It came out of his mouth not nose”.

“When I saw it I thought it was a tooth lol,” insisted another.

Earlier in the day, Williams had taken to the pitch to perform with fellow singers Nicole Scherzinger and Laura Pausini.

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Italian singer Pausini told the BBC she had goosebumps when Williams invited her to sing alongside him at the global event.

Williams emerged onto the pitch in a bedazzled tracksuit alongside Scherzinger and Pausini to sing the first ever official FIFA anthem.

The track was written by Williams, who last summer was announced as the official Music Ambassador for the global football governing body.

Williams’ performance received a mixed reception from viewers, many of whom couldn’t get over the star’s outfit.

“Robbie Williams singing at the wc final in a royal blue bedazzled glittery tracksuit in all seriousness is killing me”, commented one.

“Robbie Williams homage to Paulie Walnuts at the World Cup Final in New Jersey,” laughed another.

Despite the array of singers and Hollywood stars that joined in the celebrations, including Madonna and Justin Bieber, not everyone was pleased with the final result that was put on display for the world.

Former England player Wayne Rooney, who was part of the commentary team for the BBC, gave his instant reaction: “I like a lot of them artists, but I thought it was crap.”

After the performances, Hollywood legend Tom Cruise took to the stage to introduce the match.

“From every corner of the globe, we have witnessed greatness, and we have shared in moments of joy,” he told the crowd. “Football is a language spoken without words, a force that unites people.”