Two Liberal MPs have clashed over Peter Dutton's comments about Lebanese Muslim migrants to Australia, days after the Immigration Minister criticised the refugee policies of former Liberal prime minister Malcolm Fraser.

And while Prime Minister Malcolm Turnbull praised his minister's performance, he dodged questions about debate in Tuesday's partyroom and stopped short of endorsing Mr Dutton's suggestion last week that Mr Fraser's policies were partly to blame for Australia's struggle with foreign fighters travelling to international conflict zones.

On Monday, Mr Dutton doubled down on those comments during question time when pressed by Opposition Leader Bill Shorten on "which group of people, from which country, does the Minister believe should not have been allowed into Australia"?

Mr Dutton replied: "The advice I have is that out of the last 33 people who have been charged with terrorist-related offences in this country, 22 of those people are from second and third-generation Lebanese-Muslim background."