The plan, which has been announced by First Minister Mark Drakeford, would see Wales ease restrictions at least a week earlier than had previously been expected.
It comes as the country's hospitality sector prepares to reopen for outdoor service next week (26 April).
Speaking to BBC Radio Wales, Drakeford said: "It is my assessment that the hospitality sector - bars, pubs, restaurants and cafes - will be able to open indoors from May 17, together with all other tourist accommodation, indoor entertainment and attractions."
However, he added that it would be for the next Welsh Government to confirm the 17 May arrangements when the next three week review is held on 13 May, a week after the 6 May Senedd election.
UKHospitality's executive director for Wales, Dave Chapman, said: "UKHospitality Cymru warmly welcomes the announcement of indoor hospitality opening in Wales from 17 May, at least a week earlier than previously thought," says Dave Chapman, UKHospitality's executive director for Wales.
"We have led the calls for earlier reopening and have been advising, consulting and negotiating on the need to help protect jobs and businesses – and the public – by opening up our scrupulously regulated licensed premises, to look after undoubted customer demand as soon as possible.
"This aligns us with England and Scotland, offers clarity and commercial hope and reflects positively the medical evidence."