The further easing of restrictions raises the possibility that some festivals could take place within the coming week, the Minister for Arts has said.
Catherine Martin said live entertainment events have different requirements to sports and events of over 5,000 people in an audience need a licence from a local authority to ahead, which is why a roadmap was so essential.
From next Monday, organised indoor events and mass gatherings will return, with specific guidelines in place.
Speaking on RTÉ's Today with Claire Byrne, Minister Martin said it is a "massive step in the right direction".
She also said the reopening of nightclubs has been signalled for the end of October, but that a pilot event will happen before that and details will be announced in the coming days.
The minister said she wrote to the festival organisers and said she believed the decision to cancel the event was due to the planning requirements.
However, she said, there are other possibilities available now to venues, which means there is the possibility of festivals taking place within the next few weeks.
On the issue of capacity at this year's All-Ireland Senior Football Final in Croke Park, the minister said it would be difficult, at this stage, to ensure that all ticket holders were fully vaccinated and therefore increase capacity to 75%.
Separately, the World Health Organization's Special Envoy on Covid-19 said the virus is not showing signs of going away and that as societies "loosen up and re-start life" they should "bear in mind this virus is capable of returning".
Speaking on the same programme, Dr David Nabarro said that a sequence of surges of the virus are happening in Europe and will go on happening and that it looks like some new variants may be better able to penetrate vaccine defences.
The WHO has said it is monitoring a new coronavirus variant known as "Mu", which was first identified in Colombia in January.
Mu, known scientifically as B.1.621, has been classified as a "variant of interest".
Dr Nabarro said the WHO recommends that children over 12 should be treated in the same category as an adult regarding mask-wearing and that it is absolutely critical to keep an eye on much virus is circulating in the community.
Booster vaccines should be given to "those who really need them" and holding off for the rest of the population while other countries get vaccinated.
Dr Nabarro also said he is "really satisfied" with the public health advice provided in Ireland and that Chief Medical Officer Dr Tony Holohan and others are "doing the right balancing act".