THE opposition immigration spokesman, Scott Morrison, urged the shadow cabinet to capitalise on the electorate's growing concerns about "Muslim immigration", "Muslims in Australia" and the "inability" of Muslim migrants to integrate.

Mr Morrison's suggestion was made at a meeting in December at which shadow ministers were asked to bring three ideas for issues on which the Coalition should concentrate its political attack during this parliamentary term.

The Herald has learnt several colleagues, including the deputy leader, Julie Bishop, and the former immigration minister Philip Ruddock, strongly disagreed with the suggestion, pointing out that the Coalition had long supported a non-discriminatory immigration policy and saying it was not an issue that should be pursued.

But after Mr Morrison's comments this week on the cost of asylum-seeker funerals and his role in the controversial decision to cut a Howard government program to fund schools in Indonesia, colleagues are privately questioning whether he is trying to pursue an anti-Muslim political strategy unilaterally.

Even though the Opposition Leader, Tony Abbott, initially backed his stance on the cost of the funerals, Mr Morrison apologised yesterday for the "timing" of his comments, saying it was "inappropriate" and "insensitive" to make the remarks on the day the funerals were taking place.

Sources say Mr Morrison told the shadow cabinet meeting on December 1 at the Ryde Civic Centre that the Coalition should ramp up its questioning of "multiculturalism" and appeal to deep voter concerns about Muslim immigration and "inability" to integrate.

The sources say Mr Ruddock, the shadow cabinet secretary, was particularly "blunt" in his rejection of the suggestion, saying a well-run and non-discriminatory immigration policy was essential for nation building.

Others said they had picked up on strong anti-Muslim sentiment in their electorates but thought running a campaign against Muslim immigration could be "misconstrued".

Mr Morrison declined to comment on the discussion.

Speaking about the furore over the cost of the funerals, Mr Morrison told Sydney radio: "There is a time and a place … if you step over the mark I think you have got to say so, and I'm prepared to do so, but the government should not take that as a leave pass.

"Timing in terms of comments is very important … the timing of my comments was insensitive and inappropriate."

And Mr Abbott thanked Mr Morrison for admitting that "perhaps we went a little bit too far".

The comments sparked a backlash from Liberal moderates, with the shadow treasurer, Joe Hockey, calling for compassion and the backbenchers Judith Troeth and Russell Broadbent distancing themselves from Mr Morrison's stance.

The Treasurer, Wayne Swan, said the Coalition was "stealing sound bites from One Nation".

This week the Liberal backbencher Gary Humphries tabled a petition, signed by three people, calling for a 10-year moratorium on "Muslim immigration".