The Morrison government is being warned against thinking a one-off increase to pension payments will appease older Australians worried about losing their incomes, as retiree groups call for a permanent fix to the "trickery" in the pension system.

Days away from a decision on payments for 770,000 people, the government is being urged to make a lasting change to ensure fairness in the rules rather than relying on a single payment boost to fix the problem.

Assistant Finance Minister Zed Seselja said the government was listening to the concerns of pensioners. Credit:Rohan Thomson

National Seniors Australia is demanding a new regime to set the "deeming rate" on the private income earned by part-pensioners and allowance recipients, arguing the power to decide the payments should be given to an independent agency.

The call adds to pressure on the government to reduce the headline deeming rate from 3.25 per cent at a time when official interest rates have fallen to 1 per cent and part-pensioners have lost earnings on their term deposits.