Labor to support some welfare cuts

The opposition says it will back some federal government cuts to the welfare budget but fiercely oppose changes amounting to an attack on the vulnerable.

Federal Labor has flagged it will back some Abbott government budget measures limiting welfare spending.

It will clear the way for changes to a lower primary income threshold for the Family Tax Benefit B, pauses in asset tests for student payments, pensions and for all working-age allowances, and indexation of the clean energy supplement.

But the Labor caucus on Tuesday reconfirmed its opposition to a range of other measures it describes as "cruel cuts".

They include axing the seniors supplement, freezing Family Tax Benefit rates and pushing those under 25 from Newstart onto the lower Youth Allowance.

"Labor will oppose these cruel measures because we believe in fairness," opposition families spokeswoman Jenny Macklin said in a statement.