Enda Kenny has admitted official figures for the Irish economy are inaccurate.
As experts lined up to dismiss a claimed 26% spurt in the economy last year, the Taoiseach said the numbers can be exaggerated.
"They don't reflect accurately what is happening in the Irish economy," he told the Dáil.
But he said the latest Central Statistics Office figures were unprecedented and down to a number of "exceptional" factors during 2015.
Critics say a better system for gauging the economy is needed to allow the government to best plan how it spends public money and imposes taxes.
Nobel prize-winning economist Paul Krugman has branded the latest official Irish figures as "leprechaun economics".
Concerns have also been raised about Ireland's international reputation regarding widely-derided official figures.
Fianna Fáil leader Micheal Martin said the official economic growth rate does not reflect what is happening to real people around the country.
"Nobody believes the figures," he said.
The "absolutely farcical" nature of the figures are also "damaging Ireland's international reputation", Mr Martin told the Dáil.
Citing comparisons to Soviet Russia and China, Mr Martin called for a new system to be devised that better reflected what is actually happening in the country.
Mr Kenny said the relocation of multinationals to Ireland, aircraft leasing and developments in the manufacturing sector last year skewed the latest figures.
But he insisted a growth in jobs, rising consumer spending and taxes "confirm a strong recovery rooted in the domestic economy here in Ireland".