TDs have been told they must wait two weeks to find out when planned welfare increases will take effect.
Budget 2017 brought a €5 increase to the state pension and one-parent family payment, as well as the carer’s, jobseeker’s and disability allowances.
Unemployed people under 26 will get smaller rises ranging from €2.70 to €3.80, depending on age.
The changes are due to be introduced in March, subject to the passage of the Social Welfare Bill.
But Taoiseach Enda Kenny today refused to clear up the confusion and confirm when exactly they will kick in.
Labour leader Brendan Howlin described it an unsatisfactory position, saying TDs needed to know the precise date on which the increases are to be made.
"The Taoiseach and I worked together for five years and even in the worst of times, we did not publish a budget document without knowing the precise figures,” he said.
In response, Mr Kenny explained the relevant bill will be published in two weeks and that the costings are all fully available.
"People say they would like to have the payments made as early as possible in the new year but all these things cost money," he said.
"The government did not have an endless pot at its disposal.
"The position is that the bill will be published in two weeks. I hope it receives the support of all members because so many people receive a universal payment.
"The details and dates will be available when the bill is published and processed."
There has been a mixed response to new social welfare measures announced yesterday, with some expressing concern over the delay in increases.
The Irish National Organisation of the Unemployed said the rise in the jobseeker's allowance would have been more welcome had it commenced in January, the traditional starting point for such changes.