The JP McManus Pro-Am has been postponed and will now take place in July 2021.
The sold-out tournament was due to be held at Adare Manor in Co Limerick this summer.
A star-studded line-up including Tiger Woods, Phil Mickelson, Sergio Garcia, Jon Rahm, Rory McIlroy and Justin Rose, were set to take to the course alongside Hollywood stars Mark Wahlberg, Hugh Grant and Jamie Dornan, who were among the list of confirmed amateurs.
All tickets purchased will be valid for the rescheduled event, which will go ahead on 5 and 6 July at the same venue.
"We're all very disappointed with this news and we would like to thank everyone involved with the Pro-Am for their understanding and patience," said McManus.
"To all ticket holders, please hold onto your ticket caps and we look forward to seeing you in 2021 for what promises to be an exciting tournament of world-class golf.
"We would also like to convey our gratitude to the European Tour for their continued support of the event. We hope everyone will stay safe during these unprecedented times."