Taoiseach Enda Kenny says it is "wrong" and "not acceptable behaviour" for banks not to pass on interest rate cuts on their standard variable rate mortgages.
Mr Kenny said the bailed-out banks were restructured and recapitalised by taxpayers for the benefit of customers.
Bank of Ireland and Ulster Bank ruled out any imminent rate cuts for customers with standard variable rate mortgages this week.
Mr Kenny was speaking at the launch of the Government’s quarterly report in Dublin on their action plan for jobs.
“It is wrong that banks do not pass on lower interest rates,” he said.
“From any moral point of view, from any ethical point of view, when banks are now restructured and on their way to making profit again, it is just not acceptable that when they themselves can borrow at much cheaper rates, that they continue to have higher rates applied to mortgage holders.”
Tánaiste Joan Burton added it might have “slipped their minds” that people had their wages cut considerably to fund the recovery of banks.
“Gratitude will only get you so far with the banks. I’ve never known bankers to be a particularly grateful sort of people,” she said.
"We're all aware of the fact that people who have a variable rate mortgage in Ireland are playing an awful lot more than people who have similar financial products right across the European Union. "
Ms Burton also spoke about the Siteserv sale and said she was pleased a retired judged would oversee the review of IBRC.
“Following my discussion with the attorney general, I’m very happy that a judge has been appointed to oversight the work that’s going to be done by the liquidators,” she said.
“That’s an appropriate way, so if there are any conflicts of interest they can be addressed.
“We don’t want to move back to 10-year tribunals, which cost the country a huge amount of money and, very often, people have forgotten what they were about by the time they report.”
She said the report would be available by the end of August this year.