The Taoiseach Micheál Martin has accused opposition parties of suggesting silver bullets for the COVID-19 crisis that do not exist.
It comes as the Government is under pressure over access to both PCR and antigen testing.
With no PCR test bookings available online in 10 counties on Wednesday morning, pressure has been on health and Government officials.
The head of the Health Service Executive (HSE), Paul Reid, says they are dealing with unprecedented demand.
"If you look at the past six to seven weeks, over a million PCR tests have been completed.
"And these are phenomenal numbers in proportion to population".
The Deputy Chief Medical Officer Dr Ronan Glynn says no testing service could deal with the current level of people looking for a PCR test.
"From our data, it appears that somewhere between 10% and 20% of adults and children in this country have had flu or cold or COVID like symptoms in the past week - that’s around 700,000 people.
"There's no testing system in the world that's going to be able to manage that demand. At a point in time, the system is going to have to prioritise.
"Of course we're trying to up the testing and get people tested as quickly as possible... but ultimately the test is not the public health intervention."
The HSE says it has moved to increase staffing and is taking test capacity from private labs.
In the Dáil the Taoiseach has been pressed on when subsidised antigen tests will be available.
Mr Martin did not give a date - and accused the opposition of treating antigen like a silver bullet.
"There's no one silver bullet, Deputy, and that's the point I'm making.
"And we are, as I have said, in terms of antigen testing, there has been a significant expansion of the use of antigen testing", he says.
NPHET is due to meet on Thursday to assess the current situation, with Dr Glynn saying it is too early to know if more restrictions will be needed.
Additional reporting: Jack Quann