Updated EU COVID-19 Certificates, to reflect booster doses, are expected to be sent out on Thursday evening.

Minister of State for eGovernment, Ossian Smyth, says the vast majority of these will be sent by e-mail.

It comes as rules, adopted by the European Commission last month, mean the certs are only valid for travel within the EU for nine months after completion of the primary vaccination schedule.

The certs are used for inter-EU travel - while some member states also require them to access indoor bars, restaurants and other venues across the bloc.

The rules around validity were to be introduced from February 1st - however a number of states have brought the measures in early, owing to the Omicron variant.

This includes Italy and Austria.

On Wednesday, Fine Gael TD Alan Farrell said the certs would be updated by January 15th.

Good news with regard to the EU Digital Covid Cert. In line with EU commitments, the certs will be updated to reflect third doses, by January 15th.

— Alan Farrell TD (@AlanFarrell) January 5, 2022

While Minister Smyth told Newstalk Breakfast things will start moving even sooner.

"What we're doing is we're issuing new COVID Certs to everybody who's received a booster shot, so they can continue to travel internationally after the 1st of February.

"I can tell you today that we are expecting to start sending those out tonight, the vast bulk of them will go out by e-mail.

"So if you've had a booster shot - more than two million people have had booster shots in Ireland - you would be receiving your updated Digital COVID Cert very soon, and you can use that for international travel".

And he says those who do not have e-mail will receive a text message.

"If you are somebody who doesn't have an e-mail address, or you went to the GP and the GP didn't collect your e-mail address, you'll get a text with step-by-step instructions for how to download your COVID Cert".