The IRFU has told players and provinces that it will be next month at the earliest before they can return to collective training.
There had been tentative plans for the four provincial teams to return to collective training on 18 May, but under the Government's roadmap to lift restrictions, non-contact small group team sports training cannot start before 8 June.
Professional players will now continue to train at home, with the IRFU promising a further update next month.
A statement from the IRFU read: "The IRFU has confirmed to players that they will not be returning to training on May 18th and that we will contact them in June with further information, based on government guidelines."
Rugby is listed under phase five of the Government's roadmap to lift restrictions, which could potentially mean a return for the sport on 10 August, but that would likely be under some heavy restrictions.
Ireland had been due to take part in a two-Test tour of Australia in July and while that Tour has not yet been officially cancelled, it is difficult to see a way in which is could go ahead.