Right-wing poster boy Milo Yiannopoulos has had his visa rejected and told he cannot enter Australia.

The British firebrand was barred from entering the country earlier this week, with the Morrison government fearful his views would spark violent protests should he hold a speaking tour.

He now has a month to appeal the decision to the Department of Home Affairs, which said the ban was made on 'character grounds'.

Scroll down for video

Right-wing firebrand Milo Yiannopoulos (pictured) has had his Australian visa rejected

Yiannopoulos was due to deliver a speaking tour last December with far-right commentator Ann Coulter but cancelled 'due to unforeseen circumstances'.

A letter sent to the 33-year-old by immigration authorities a month before the official decision was handed down gave an insight into the way they were leaning.

One of Yiannopoulos' strongest supporters, Andrew Bolt, shared the letter during a television broadcast for Sky News.

The letter explicitly made note that Australia had the power to block someone on the grounds of a fear they could 'incite discord in the Australian community or in a segment of that community'.

The Morrison government rejected the application over concerns his tour could incite violence

Yiannopoulos' supporters clashed with protesters during a speaking tour in Melbourne and Sydney in 2017.

Heavily armed police were forced to intervene and break up brawling groups, using capsicum spray on dozens of people.

Yiannopoulos also incited controversy last June when he was suspended from Paypal for sending $14.88 to a Jewish journalist.

The number 1488 is commonly used by white supremacists and neo-Nazis as a substitute for 'Heil Hitler'.

He now joins a number of right-wing speakers who are banned from conducting tours in Australia, including WikiLeaks whistleblower Chelsea Manning and Gavin McInnes, the leader of the far right Proud Boys group.

The last time Yiannopoulos held an Australian speaking tour, protesters clashed on the streets

One Nation Senator Pauline Hanson threw her support behind Yiannopoulos, saying banning him would be a violation of free speech.

'You may not agree with everything that they say as long as they don't go out there and advocate violence,' Ms Hanson told on Sky News Australia on Tuesday.

'If you actually want to stop someone. Stop the protesters with their violence.'

She said she had contacted Minister for Immigration David Coleman through letters, texts and phone calls - unsuccessfully urging the government to grant Yiannopoulos a visiting visa ahead of his second Australian tour.