A UFC event that had been scheduled to take place at the 3Arena in Dublin in August has been cancelled.
Under the revised Phase 3 of eased lockdown restrictions, 50 people will be allowed to gather indoors from 29 June, rising to 100 by July 20.
Tickets had been due to go on sale this Friday.
"Due to current government restrictions on public gatherings in the Republic of Ireland, UFC Fight Night originally scheduled for 15 August will not take place as planned at the 3Arena in Dublin," the official UFC Europe account tweeted on Wednesday.
"UFC looks forward to returning with an event in the near future."
Earlier this month UFC president Dana White promised "an experience that none of us will ever forget" after it was announced Yas Island in Abu Dhabi will host four of the organisation's events in July.
The UFC has been able to hold a number of cards behind closed doors during the pandemic - all of them in the USA.
It plans to head to the United Arab Emirates resort which will produce UFC 251 on 11 July 11 followed by three Fight Nights on 15, 18 and 25 July.