UK tourists stranded in Bali are being advised to avoid exclusion zones after an erupting volcano caused the island’s international airport to close.
The Foreign and Commonwealth Office also urged holidaymakers to contact their travel company and monitor local media reports in an update to its travel advice.
Indonesian authorities have issued the most serious level of alert for Mount Agung, which has been hurling clouds of ash into the atmosphere since the weekend.
They reported that the volcano’s explosions are being heard more than seven miles away, and a larger eruption is possible.
An exclusion zone has been created about six miles from the crater.
Ash caused the island’s Ngurah Rai Airport to close on Monday until at least 7am local time on Tuesday, causing the cancellation of 445 flights.
Around 330,000 British nationals visit Indonesia every year, with many heading to Bali for its beaches, green landscape and Hindu culture.
Bali is a popular destination during Christmas and new year, but November is not a high season for tourism.
UK travel trade organisation Abta said there “will only be a relatively small number of UK holidaymakers on the island at this time of year”.
But it warned that volcanic ash clouds could result in further airport closures.
“Anyone due to travel to the region imminently should check with their travel provider or airline to establish if their holiday or flight is affected,” an Abta spokeswoman said.
In 2010, an eruption of a volcano in Iceland produced an ash cloud that caused a week of aviation chaos - with more than 100,000 flights cancelled across the UK and the rest of the world.
Bali’s Mount Agung is around 44 miles from the nearest major tourist hotspot of Kuta.
Travel firm Kuoni said in a statement: “We’re monitoring the situation closely and have been in touch with all our customers who are currently in Bali to update them of the situation.
“All our customers are in tourist areas which are safe and unaffected by volcanic activity and well away from the evacuation zone.”
Some Kuoni holidaymakers are due to leave the island on Friday.
The statement added that “everyone is calm and continuing with their holiday as normal”.
There are no direct flights between the UK and Bali, with journeys involving at least one connection.
UK travel firms are not obliged to modify the conditions of flights and holidays until the FCO warns against visiting the island.
Singapore Airlines, which operates flights to Bali from London Heathrow via Singapore, is offering passengers with bookings between now and December 4 the opportunity to obtain a refund or postpone their trip up to the end of January.