Taoiseach Micheál Martin has said the strategy of a "circuit breaker" lockdown to address rising cases of Covid-19 is experimental and he is not convinced any such move would be a temporary move.

Speaking to RTÉ News, Mr Martin said he was not sure it was possible to shut everything down for two weeks and "come back as normal".

He said there was a chance and an opportunity for Level 3 restrictions to have an impact, but it depended on our behaviour.

Mr Martin also said that keeping schools open was a priority for the Government.

Writing in Today's Sunday Independent, Tánaiste Leo Varadkar said a circuit break "may well be needed", but outlined a series of questions around how it would be implemented and what the objective would be.

"The problem is that when you are in a full lockdown it is very hard to get out of it," the Tánaiste wrote.

Minister for Health Stephen Donnelly earlier told RTÉ's This Week, that it needs to be understood that for the next two weeks the figures will get worse, but at the moment a 'circuit breaker' is not being considered.

However, he said, it may be possible in the future that the country may need to move to Level 4 or 5.

Mr Donnelly also confirmed that Ireland will sign up to the European Union's "traffic light" system for travel this week but he said airport testing will not be rolled out at this stage due to current capacity levels.

Mr Donnelly said "any testing capacity needed for travel will be over and above what we already have" and he said plans are currently being worked up in detail at the moment.

He said the Departments of Transport, Health and Foreign Affairs are examining what capacity will be needed and they are working through the testing options and the protocols.

"We are exploring PCR testing, which is the gold standard and the system that is currently used in Ireland, and we are exploring the use of antigen or lamp testing, which is essentially a rapid test."

Mr Donnelly insisted that "testing at airports will happen because it is required as part of the protocol".

Under the traffic light system, people travelling to or from counties in the green category will not be required to restrict movements or to self-isolate.

Mr Donnelly said: "For amber and red counties, the default positions around Europe will be that you need to self isolate or restrict your movements."

He said the Government is looking at "what testing protocols can be put in place, so that the need to restrict your movements doesn't happen".