Justin Bieber has responded to Sharon Osbourne’s comments that 'he won’t stand the test of time.'

The former X-Factor judge told a national radio conference in Sydney last week that the Canadian teen idol’s career wouldn’t last because his audience would eventually outgrow him.

The 18-year-old then appeared to allude to her criticism on his Twitter page, posting, "doubt me....i like it," before adding, "im working on something special."

Bieber then addressed Osbourne specifically, posting a link to his new video, 'Beauty And & Beat,' with the words, "Not worried sharon."

Watch the video for 'Beauty And A Beat' below: