Updated 2.59pm: Anti-Islamisation and anti-racism groups have clashed at rival rallies across Australia.

A group calling itself Reclaim Australia held rallies to oppose sharia law and halal tax.

Controversial politician Pauline Hanson spoke at the Brisbane rally and says Australians have a right to speak out.

"We don't like Islam. We're in fear of what Islam might do to our country, our culture, our way of life. And it is impacting in different areas of our society."

The Federal Opposition leader in Australia says any suggestion that Muslims are planning to bring Sharia law to Australia is exaggerated.

"50-60 years ago, people said that the Irish Catholics were trying to take over the joint, and that wasn't true either. What we've got to be careful of is putting all people in a minority group, and saying they're all the same and they're signing up to bad ideas. That just isn't true."

Bill Shorten says no one has the right to violence after rival groups clashed at rallies cross the country yesterday.

Organiser Daniel Evans says they're not against Muslims but the totalitarian ideology that comes from Islam.

"We're just hoping the government will take notice of this and starts to do things, but it's already on the table now."

Among those at the counter rally was John Passant from the Refugee Action Committee.

"We weren't going to be putting up with a racist demonstration and rally in Canberra."