Sinn Féin has launched a Bill which would prevent bailed-out banks from hiking mortgage interest rates without the Financial Regulator's approval.
The Interest Rates Approval Bill, would force the regulator to weigh-up the impact of rate increases on the taxpayer as well as the bank's commercial interests.
AIB will next week increase its variable rate by 0.4% - its third rise in 12 months.
Sinn Féin's Finance Spokesperson Pearse Doherty said that the move is unjust - and it is time the banks treated taxpayers fairly.
"We have to remember and very mindful that €64bn of Irish tax payers money has been injected into these banks," he said.
"It is wrong for banks to continually hike up interest rates in the intent to make profits on the back of ordinary people particularly at a time when there is a huge mortgage crisis."