The Tiwi Land Council has enforced restriction of entry to the islands, located off the coast of the Northern Territory 85 kilometres north of Darwin.
The measures will come into effect on Thursday night as the islands explore all options to protect the remote communities.
The land council announced that as of 7pm on Thursday night communities on Bathurst and Melville Island will be closed.
Wurrumiyanga (Nguiu), Wurankuwu (Ranku), Milikaptiti (Snake Bay), and Pirlangimpi (Garden Point) will come under the new restrictions.
The closure of the areas across both islands includes public access to homelands and the Tiwi College at Pickataramoor.
Any person who is not a resident or personnel required to deliver emergency or essential services has been asked to leave the islands.
The new announcement extends previous restrictions, introduced by the land council on March 18, to include the docking of passenger boats and arrivals of passenger aircrafts.
Tiwi families are also strongly advised to restrict their travel outside of the islands.