The Abbott government will exclude the age pension and family tax benefits from its review of the welfare system, with Social Services Minister Kevin Andrews indicating he will target unemployment benefits and disability pensions.

Warning the system risked becoming ''unsustainable'', Mr Andrews commissioned former Mission Australia head Patrick McClure to conduct a ''broad'' review of payments, which were worth more than $70 billion a year.

Kevin Andrews: Targeting unemployment benefits and disability pensions. Credit:Rebecca Hallas

But the age pension - which at $36 billion last financial year accounted for about half of all welfare spending - would not be examined in the review.

Nor would the review consider Family Tax Benefits Parts A and B, which cost $19 billion last year, or Mr Abbott's $5.5 billion-a-year paid parental leave scheme.