Tony Abbott says comments made by a spokesman for Muslim group Hizb ut-Tahrir could fall under proposed counter-terror legislation considering that same system prosecuted conservative commentator Andrew Bolt for his "relatively mild" article.

The prime minister made the comments during an interview on 3AW Radio this morning, when he was asked to respond to a heated exchange between Hizb ut-Tahrir spokesman Wassim Doureihi and journalist Emma Alberici on ABC's Lateline program.

Mr Doureihi had refused to denounce the violent tactics of Islamic State fighters and got into a tense debate with Alebrici about her line of questioning.

Mr Abbott, who yesterday said Hizb ut-Tahrir may be subject to proposed new laws that will make it an offence to promote terrorism, said the interview raised further concerns.

"This is an organisation that is very careful to avoid advocating terrorism but is always making excuses for terrorist organisations," he said.

"I regard it as un-Australian."

Host Neil Mitchell later asked the prime minister whether the comments made on Lateline would fall under proposed new laws to ban the promotion of terrorism.

“Well certainly if poor old Andrew Bolt is prosecuted for a relatively mild piece…” Mr Abbott said.

"If we are looking for objectionable speech, the kind of stuff we are hearing from Hizb ut-Tahrir is infinitely more objectionable than anything you'd ever hear from Andrew Bolt."

He also rejected Mr Doureihi's claim that Australia was complicit in the deaths of many of Muslims around the world.

"What we’re doing id defending millions of Muslims from the murderous rage of ISIL,” Mr Abbott said. “That’s what we’re doing; that’s what we were hoping to do in Afghanistan."

Member of controversial Muslim group and ABC reporter in heated exchange over IS: