Australians flying to and from Bali are being urged to check their airlines' websites on Friday morning after Mount Agung began spewing water vapour and ash into the atmosphere, disrupting travel.
Flights between Sydney, Melbourne and Perth and the tourist island have been delayed, cancelled and turned back because of renewed activity at the Indonesian volcano.
More than 20 flights across Jetstar, Qantas, Virgin and Air Asia were disrupted between Thursday night and Friday morning due to the ash cloud moving toward Denpasar airport, which is now closed.
Virgin cancelled two flights between Sydney and Denpasar on Thursday and said another scheduled to depart the island on Friday morning faced delays.
The airlines are awaiting an update from the Volcanic Ash Advisory Centre due at 9am on Friday.
The Mount Agung volcano began shooting ash 2,000 metres into the air on Thursday.
The regional volcanic ash advisory centre in Darwin said winds could carry the ash southwest toward Bali's international airport and Java, Indonesia's most densely populated island.
Mount Agung is about 70km northeast of Bali's tourist hotspot of Kuta.
It's last major eruption was in 1963 and killed about 1,200 people.
Activity at the volcano was high last year and forced the evacuation of tens of thousands of people, but it had been quieter this year.
Indonesia, an archipelago of more than 250 million people, sits on the Pacific "Ring of Fire" and is prone to earthquakes and volcanic eruptions.
Local government seismologists monitor more than 120 active volcanoes.
Australian Associated Press
