Australian travellers are being warned to check their flights before heading to the airport after a major volcanic eruption in Indonesia triggered widespread cancellations and airport closures.

Mount Anak Krakatau, in the Sunda Strait between Java and Sumatra, erupted over the weekend, sending volcanic ash as high as 50,000 feet into the atmosphere. Eight airports across Indonesia have been affected, including Jakarta’s Soekarno-Hatta International Airport, which temporarily suspended operations as ash spread across parts of western Indonesia.

More than 1500 flights have been suspended across the affected airports, disrupting travel plans for about 170,000 passengers, according to Reuters.

Australians are among those caught up in the chaos with passengers travelling from Melbourne and Sydney to Jakarta unable to fly as scheduled on Saturday night, the ABC reported.

Qantas has confirmed flights QF39, QF40, QF41 and QF42 have been affected by the eruption.

The airline is offering additional flexibility to eligible passengers booked to travel to or from Jakarta between September 5 and 9, including fee-free refunds, travel credits or date changes.

The Australian Government has also updated its travel advice for Indonesia.

Smartraveller warns airports in affected areas may close at short notice, while further flights could be delayed or cancelled.

Australians with upcoming travel plans should monitor their flight status and confirm any changes directly with their airline or travel provider before leaving for the airport.

Volcanic ash can pose a serious danger to aircraft, potentially damaging engines and other systems. The ash is also affecting air quality, with Australians who have asthma or other respiratory conditions advised to take extra care.

Despite Anak Krakatau’s violent history, Indonesian authorities say there is currently no tsunami threat and no casualties have been reported.

The volcano emerged from the caldera created by the catastrophic 1883 Krakatau eruption. A partial collapse of Anak Krakatau in 2018 triggered a tsunami that killed more than 400 people.

Authorities continue to monitor the volcano as airlines work through the flow-on disruption.