A briefing paper delivered to the Turnbull government amid a politically fraught debate on immigration warns cutting the current intake risks costing the federal budget billions of dollars, lowering economic growth and damaging the living standards of Australians.

The migrant intake from 2014-15 alone will provide a $10 billion boost to the budget over the next five decades, the newly released Treasury and Home Affairs analysis found. It warned of "far reaching effects" of significantly lower economic growth if the current rate of migration is not maintained.

The document adds a new dimension to disagreement inside the Coalition over whether Australia's 190,000 annual migration cap is to high. Former prime minister Tony Abbott has called for a cut of 80,000, while Home Affairs Minister Peter Dutton privately canvassed a reduction of 20,000 before the idea was eventually ruled out. Other senior ministers, including Treasurer Scott Morrison, have publicly pushed an unashamedly pro-immigration policy.

The briefing, ordered by Treasury secretary John Fraser and Home Affairs secretary Mike Pezzullo in 2017 but delivered this year, found migrants boost the Australia economy by up to 1 per cent per year and those who have arrived since 1996 performed better in the workforce than the average Australian-born employee.