Robert Irwin has shocked fans by debuting his bold new look - featuring a very bushy moustache.

The 22-year-old reality TV star, who is currently in South Africa filming the upcoming season of I'm a Celebrity...Get Me Out of Here took to his social media on Sunday to showcase his fresh new style.

In the clip, Robert explained that he grew a beard during a one-week break in production and shaved it off - but left the moustache.

'I'm going to take the opportunity to play a little prank on the crew,' Robert said in the amusing video, which he captioned: 'New Year. New Look.'

Robert, known for his clean-cut image, could be seen showing off his large moustache to the I'm a Celebrity team, including co-host Julia Morris, and his mother, Terri Irwin.

After Julia appeared to be less than impressed with Robert's new look, Terri jumped in to defend her boy.

'As your mother, I'm incredibly proud,' she said.

Robert later asked his mother whether he should keep the moustache, and she appeared to be in two minds, saying 'yes' while shaking her head 'no'.

He later told fans that he 'had to' shave off the moustache ahead of filming his reality show.

During the video, Robert had some fun with his new look by including images of famous faces known for their bushy upper lips.

Among the actors seen in the clip were Tom Selleck in his Magnum PI days and Nick Offerman from Parks and Recreation.

Robert also paid tribute to Top Gun - a reference to the 'Goose' character played by actor Anthony Edwards.

His look was revived by actor Miles Teller who played 'Rooster' in the sequel Top Gun: Maverick. 

Followers expressed their enthusiasm for Robert's short-lived new style on the post. 

'Robert, I just fell to my knees,' wrote one female fan, while another urged the TV star to 'keep it'.

A third person joked: 'You need to be in Top Gun 3!!!' 

It comes after Robert once again impressed his fans with his compassion for all creatures great and small.

Fresh from his US Dancing With The Stars win, Robert, returned to South Africa to get set for the upcoming season of I'm A Celebrity...Get Me Out Of Here!

He took to Instagram on Friday to share a video where he can be seen rescuing a chameleon that had wandered onto the road.

The clip began with the wildlife warrior walking up to the critter and gently picking it up.

'Alright buddy, it's ok,' he said reassuringly. 'Crossing the road, this little chameleon.'

With the cute critter now safely perched on Robert's arm, he continued: 'Isn't he so cute? He's not particularly happy with me.'