Two Irish citizens on board the Diamond Princess cruise ship have tested positive for coronavirus, the Department of Foreign Affairs has said.
It said they share dual citizenship with another EU country and do not normally live in Ireland.
They are being treated in hospital in Japan.
The tánaiste (Irish deputy prime minister) Simon Coveney said six Irish citizens were on board the vessel, which is docked off Yokahama in Japan.
The department said it was "in close contact with those who remain in quarantine on the ship" and were working with "EU partners and other like-minded countries regarding options for their return".
The Diamond Princess, with some 3,700 passengers and crew, has been in quarantine at Yokohama port since 3 February.
Nine Irish nationals are also on the Westerdam ship docked in Cambodia
The Westerdam had been stranded at sea having been rejected by five ports in Asia due to worries that passengers may have had coronavirus.
It docked in the Cambodian port city of Sihanoukville last Thursday.
Mr Coveney said that out of the nine Irish passengers, seven were currently being tested for coronavirus and the other two had returned to Ireland.
Six other Irish citizens were repatriated from Wuhan, in China - three on 31 January and the other three on 9 February.
An 83-year-old American woman tested positive after leaving Westerdam and there are fears about other passengers on the cruise, with many of them now dispersed around the world.
On Tuesday Mr Coveney , who is also the Republic of Ireland's foreign minister, told Irish national broadcaster RTÉ: "We're working with Irish nationals on both of those ships to make sure they're safe and if they're in quarantine to make sure those conditions are safe."
He added that he would not "get into too much detail as people are entitled to confidentiality" when dealing with consular services.
A British couple who have been on the Diamond Princess have tested positive for coronavirus, their son told the BBC.
Sally and David Abel, from Northamptonshire, are among 74 UK nationals on the ship.
Japanese officials said there were 99 new cases of infections on board the ship, bringing the total to 454 confirmed cases - it is the largest cluster of cases outside China.
On Monday, two planes carrying hundreds of US citizens from the ship in Japan arrived in the US.