The Taoiseach has said the AstraZeneca and Johnson & Johnson vaccines should be reconsidered for younger age groups, to fight the spread of the Delta variant, as a further 380 Covid-19 cases were confirmed this evening.
Micheál Martin believes the Delta variant has changed the balance of risk when it comes to using those vaccines.
Chief medical officer Dr Tony Holohan is also seeking wider use of the AstraZeneca and Janssen vaccines to ensure stockpiles don't go to waste.
He has written to the National Immunisation Advisory Committee (Niac) asking if these vaccines can be given to younger people, including those in their 20s and 30s.
The EU leaders had a "lengthy discussion" on COVID19, the Taoiseach said in Brussels, noting the meeting went on till 2am on Friday morning.
"The Chief Medical Officer and I spoke last week and he indicated to me he would be engaging with NIAC in respect of the application or administering of vaccines in terms of age restrictions, in particular in the context of AstraZeneca, and Janssen and that would really broaden the portfolio of vaccines available for July and August," he said.
"I think the balance of risk has changed, therefore, that's something that will be considered by the immunisation advisors to the government in terms of making sure that we can protect people against the Delta variant.
"So, a lot of data is being collected but I think that's the most practical exercise underway at the moment, consideration by the CMO and whether we can change the age restriction constraints on utilisation of Astra Zeneca and Janssen.
"But, obviously, we need to get down to the younger age cohorts and more quickly as we possibly can get them protected, and so on."
Currently, Niac recommends that AstraZeneca and the single-dose Janssen vaccines are limited to the over-50s due to concerns over very rare cases of blood clotting, but there is now growing concern that hundreds of thousands of doses will be left unused at a time when the Delta variant is posing an increasing threat to public health.
The Taoiseach also said there won't be additional supplies in July, in terms of MRNA vaccines, there may be in the in Q3 cycle, "but that's not nailed down"
"There's also some research still going on in terms of the mixing of vaccines, but fundamentally from the Irish perspective my view is, operationally what we've been doing has been very effective and very efficient coming down through the age cohorts, with a very high uptake rate."
Mr Martin added he did not feel the rise of the Delta variant would prevent the return to international travel planned for July.
Scheduled deliveries of AstraZeneca could see 500,000 doses arriving in August and again in September, but the over-50s will have largely been vaccinated.
HSE chief executive Paul Reid said he was keen to ensure vaccines were used.
"None of us want a situation where we have a stock that we are not utilising and we don't have people vaccinated. That's a situation that we'd all like to avoid."
More than 300,000 doses of vaccines are set to be administered this week and next.
Mr Reid said there is a "very real threat” across Europe from the Delta variant, which originated in India, and it is “inevitable” cases will rise here too.
“We are flagging today a very real threat across the world and across the EU, which the European Centres for Disease Control is reflecting on, and which we are seeing in the north of Ireland, and seeing in the UK.”
Mr Reid said it is hard to imagine going back to the “dark days” of January due to the vaccination programme.