An Australian university has cancelled a planned lecture by a Muslim activist after it discovered he had links to an international extremist group.

Uthman Badar is the Australian spokesman for international group Hizb Ut-Tahrir (Party of Liberation), which seeks a caliphate – or Islamic state - based on Sharia Law.

He had sparked outrage in Sydney recently when he planned to give a talk at an arts festival titled "Honour Killings are Justified".

He had been invited by the University of Western Australia’s Muslim Students Association at a lecture titled "The Crisis in Gaza" on Saturday.

The association’s Nazim Khan reportedly said he was not aware of Badar's links to the radical group when he booked the activist.

He said the association moved quickly to cancel Badar's attendance when it was made aware of his views.

"The booking was made by one of our trusted associates from outside the university... and we did not do our due diligence," Khan was quoted as saying by The West Australian.

"When we found out who the speaker was and his background we chose to cancel it."

In a letter to the university’s vice-chancellor, Paul Johnson, the association’s executive officer wrote: “I want to inform you that I am cancelling the talk scheduled for this Saturday at UWA by Uthman Badar.

“We expect anyone who comes to the university – whether they are a member of staff, a student or visitor – to abide by the university’s code of ethics and code of conduct.”

Those ethics included “very clear ethical principals about equity, justice, respect for people and a commitment to diversity”.

Anti-Islamic tensions have risen in Australia in recent weeks, leading Prime Minister Tony Abbott to meet with some groups in Melbourne to discuss their travel bans.

Some Muslim groups last week said they were boycotting the well-established Sydney Morning Herald newspaper after it suspended a columnist who swore at readers complaining about his opinion piece and an accompanying cartoon about the war in Gaza.