“A free society cannot tolerate its tolerance being trampled on,” she told the Austrian Press Agency.

She said that she supports a suggestion from Greens councillor Efgani Dönmez to create a law banning radical Islamic movements in Austria, but said that Austria’s 1947 Prohibition Act – which is used to combat the resurgence of National Socialist activities – should be preserved as it is.

Mikl-Leitner said it was time to have a discussion about extremism and terrorism “without taboos”.

Linz’s FPÖ chairman Detlef Wimmer has said there needs to be a “practical approach” to any ban as “in some cases it will be extremely difficult to convict people of religious extremism and to prove it before a jury,” he said.

He added that it would perhaps be more effective just to remove asylum or citizenship status from religious extremists and ban them from travelling.

He also put forward the idea of a ban on extreme left-wing activists like the Black Bloc, who were responsible for the violent protests against the right-wing Academic’s Ball.  

Last week, nine suspected jihadists were arrested in Austria and put in remand custody.

According to the interior ministry, around 130 people from Austria joined wars as jihadists, some of whom had already returned. Most of them were young men without any education or job prospects, said the ministry.