The IRFU has confirmed that a proposed tour of Fiji will not now proceed due to a Covid-19 lockdown situation in the island nation.
The series was supposed to take place in the July international window, but alternative opponents are now being sought.
The IRFU said talks had been at a "very advanced stage" but that the uncertainty over what the conditions will be like in the summer made it impossible to confirm the trip.
Ireland head coach Andy Farrell said: "It is incredibly disappointing that we are not now able to tour Fiji.
"It would have been a tough rugby challenge against an excellent Fijian side and a huge opportunity for us to develop as a group and build on the progress made during the past year.
"Touring is such an invaluable experience in terms of what we learn about the group and that is why the IRFU worked tirelessly with Simon Raiwalui, the high performance general manager of Fiji Rugby to make the tour a reality and it is such a shame that it can now not go ahead.
"We will be looking to source alternative fixtures and we hope to have them nailed down in the coming weeks."
Ireland are due to play New Zealand, Argentina and a tier 2 nation in the autumn but these fixtures have not yet been confirmed.
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