Sinn Féin has said a mortgage interest relief measure should be brought in until the end of the year.
The party's Finance Spokesman Pearse Doherty was speaking following another rate hike from the European Central Bank (ECB) last week.
Taoiseach Leo Varadkar has said mortgage interest relief will be considered as part of Budget 2024.
Deputy Doherty told The Hard Shoulder any relief should happen sooner.
"We have seen seven increases in the space of 10 months by the ECB - pushing up the interest rate and the cost of maintaining or securing the roof over your head," he said.
"The Central Bank came out last week with a report, saying that 20% of all mortgage holders are paying 50% more on their mortgage compared to last year.
"What that means is they're paying, on average, €5,000 more than they were in June last year".
Deputy Doherty said the relief would 'take the sharp edge off.'
"What we're arguing for is a time-limited, targeted intervention as a cost of living measure that would take onboard a-third of that increased interest," he said.
"It doesn't insulate them from everything, but what it does do is it takes the sharp edge of this off - and then lets review it again closer to the end of the year".
He said any relief should only be applied to "the increased amount of interest you've paid since June last year."
Interest rates 'to remain high'
Deputy Doherty said universal supports have not helped those hardest-hit.
"A family sitting down last June to work out how they're going to make everything balance didn't factor in the fact that they'd be paying €5,000 or €6,000 more on their interest on their mortgage," he said.
"There has to be some type of support".
He said interest rates are unlikely to drop in the short-term.
"What you're trying to do is trying to deal with the shock of this sudden increase," he said.
"You're also trying to insulate as many families as possible from a portion of this.
"Interest rates are going to remain high, that's the reality of it, for the next number of years," he added.