Worried Justin Bieber fans have shown support for the pop star after he cancelled his meet and greets due to depression.

The 22-year-old singer was forced to cancel his personal sessions with fans prior to his stadium concerts after he expressed concerns for his mental health on Instagram on Tuesday (22Mar16).

His fans, known as "beliebers", took to social media to respond to the news in their droves, and got the hashtag "#CancelPurposeTour" trending after many decided their idol's mental health was more important than fulfilling his touring obligations.

"Maybe cancelling the tour for now is the better option?" wrote one fan.

The hashtag has been met with mixed responses, with many believing cancelling his world tour is "stupid" and would make matters worse.

"I'm not a belieber but don't ask him to cancel the tour. Encourage and support him and help him to fight through this," wrote another.

Many fans who have purchased special VIP meet and greet tickets were left dismayed after it was announced Justin would no longer be seeing fans due to a "security incident".

The Canadian star said that the previous meet and greets sessions left him emotionally exhausted, "I enjoy meeting such incredible people but I end up feeling so drained and filled with so much of other people's spiritual energy... I always leave feeling mentally and emotionally exhausted to the point of depression," he wrote on Instagram. "The pressure of meeting people's expectations of what I'm supposed to be is so much for me to handle and a lot on my shoulders."

Many fans responded initially with kind words after the news broke, using the hashtag "WeAreHereForYouJustin". One kind follower offered the advice, "Your spiritual and emotional health is critical to what you do. Your fans will understand!"

Last weekend (19-20Mar16) the Sorry singer hit out after his Los Angeles gig. Seeming strained with his hectic touring schedule, he wrote on social media, "La is so fake they drain me until im dry (sic)."

The Purpose World Tour continues on Friday night (25Mar16) in Las Vegas. He will have a break from touring between July and September (16), besides two shows at Britain's V Festival.