Pensioners will be prioritised ahead of unemployed Australians for any boost to welfare payments as the Morrison government stands firm against growing demands to lift the Newstart allowance.

Prime Minister Scott Morrison has told colleagues returning the budget to surplus is his "number one priority" and any future increase in welfare payments will be directed towards the 2 million Australians on the aged pension.

Federal ministers and government MPs dodged questions on Wednesday over revelations by The Sydney Morning Herald and The Age that a bipartisan call to increase the Newstart allowance was removed from a parliamentary report at the direction of the Coalition.

Seniors groups are among the loudest voices for a boost to the payment, with a growing number of Australians aged 55 and older directly linked to struggles in retirement.