The acting chair of the Irish Fiscal Advisory Council Sebastian Barnes said there were questions about how the State's plan to transform healthcare, called Sláintecare, would be funded.
He told the Oireachtas Covid-19 committee that the plans in the programme for government were welcome and affordable as long as the right fiscal decisions were taken.
IFAC told the committee that Sláintecare would add €3 billion annually to spending.
Representatives of the council were asked to provide further details of the estimates by Social Democrats co-leader Róisín Shorthall who said the costings were very much out of line with the figures forecast in recent years.
Mr Barnes also said there was uncertainty about the economic outlook, including how SMEs and individual households will respond to the pandemic and said restoring confidence was important.
He said part of that is having a plan for the medium term for how the economy is going to go, "for example with issues like climate change and pensions" that otherwise, he said, might hang over people like a cloud.
Mr Barnes was responding to questions from Norma Foley, Fianna Fáil TD.
Green Party finance spokesperson Neasa Hourigan asked about the impact on public finances of climate change policies.
Mr Barnes said it is very helpful that there is a clearer target in the area of climate change policies and that "hopefully the economic plans can be aligned to make sure it can be achieved in the way that is effective and consistent with the sustainability of the public finances".
Fianna Fáil TD John McGuinness said there is nothing really factual in the programme for the government, in terms of costing, that "we don't know where that programme is going to end up or indeed how much of it will be implemented".
He asked Mr Barnes if there is a commitment for no increase in taxes in the programme for government and if borrowing will continue, what is the forecast for how much Ireland will owe and how it will be paid for.
Mr Barnes said the debt was €200 billion.
Dr Eddie Casey, chief economist with the Irish Fiscal Advisory Council, said Ireland would need to borrow around €14 billion this year with an additional €14 billion next year.
