More than 56,000 people waiting for an extension of the over-70s medical card have been told they cannot be given a commitment that the promise will be honoured.
An increase in the income threshold was announced in the Budget last year, contingent on the finding of savings in the Department of Health budget.
"Obviously, savings haven't been achieved due to Covid," said Junior Health Minister Frank Feighan when asked about setting a commencement date in the Seanad.
The failure to establish the extra entitlement had "undoubtedly been a source of frustration to those people aged 70 and over who may be eligible under the new thresholds", he said.
Mr Feighan said 75pc of people over 70 have a medical card, and the potential beneficiaries of the Budget measure - an estimated 56,000 people - would result in over 88pc of that cohort becoming eligible.
Legislation was passed by the Dáil and Seanad last month, several weeks after the increased eligibility was due to come into effect on July 1.
The delay arose from the failure to properly constitute the second chamber as a result of prolonged negotiations after the general election in February.
Mr Feighan said he could not give a commitment, but would instead bring the concerns raised to the attention Health Minister Stephen Donnelly.
"This would prove to be a very beneficial measure for these additional eligible persons who will now have access to a range of health services at an affordable level," he said
Fine Gael senator Martin Conway said those aged over 70 have a "legitimate expectation that they will receive medical cards" after what was promised in the Budget last October.
Many people over 70 had been waiting to apply for their medical cards last July 1, only to be disappointed.
The budget commitments would have increased income limits for medical cards by €50 a week to €550 for a single person and €1,050 for a couple by July.
Labour senator Mark Wall said he had previously received assurances from former health minister Simon Harris that medical card reviews prior to renewal would be delayed, with medical cards extended to 2021 because of the coronavirus pandemic.
He said he dealt with a man aged 69 who had spent five months in hospital and arrived home to a letter from the Government that "was not congratulations on beating Covid or the disease he had, it was instead a renewal letter for his medical card".
The constituent's first comment was to ask if the Government wanted to put him back in hospital with stress.
Mr Feighan said the HSE had temporarily suspended all reviews of eligibility at the outset of the pandemic, extending cards for another year from March until last month.
"While periodic eligibility reviews have since resumed, it is important to recognise that the HSE operates a sensitive assessment process," he said.
"They may also exercise discretion and grant a medical card where individuals exceed the income guidelines but face other difficult circumstances such as extra costs arising from an illness."