Bali, famous for its surf, beaches and temples, attracted nearly five million visitors last year.

Tourists flock to the Hindu-dominated tropical hotspot annually, while couples hope to tie the knot at beach and cliffside retreats with sweeping views of the ocean.

Others want to get even closer to the waters teeming with colourful fish and coral.

But business has slumped in areas around the volcano since September when Agung's volcanic tremors began to increase.

Agung is one of over 120 active volcanoes extending the length of Indonesia, which perilously straddles the “ring of fire” – an area along the basin of the Pacific Ocean prone to earthquakes and volcanic activity.

And the huge volcano erupted for the first time in half a century last week sparking nation-wide panic.

As well as a series of mini explosions, the 3,000-metre high mountain has spewed thick black ash clouds into the air, forcing the closure of the international airport and the evacuation order of some 100,000 people.

Indonesia's tourism minister Arief Yahya warned that Bali could lose up to £500 million in visitor-related revenue if Agung's activity doesn't die down before the end of the year.

"There has definitely been a huge effect because of the volcano," said Ni Komang Astiti, who works at dive operator Dune Atlantis in the southeast of the island.

"We've had many cancellations because the guests can't fly to Bali."

Bali's main international airport was shut for almost three days from Monday as towering columns of volcanic ash and smoke made flying dangerous, sparking travel chaos and leaving around 120,000 tourists stranded.

It re-opened late Wednesday, but mostly for tourists departing the island, not arriving. And it is likely to lose again on Friday after several airlines cancelled flights amid fears the ash plumes would return to the aviation path.

Australian budget airline Jetstar said it would cancel nine flights on Friday after meteorological officials warned the ash could hit operations at Bali airport, about 60 km (37 miles) southwest of the Mount Agung volcano.

"If we usually have 20 guests a day, this time around it's only two people," Astiti said.

"We're worried. If there are no guests, what should we do? We depend on the tourism industry."

Volcano experts warn that the mountain, which has had a series of mini eruptions, could still produce a major blast at any moment.

"There's nothing we can do - we can only wait for the mountain to stop erupting," said I Ketut Ardana, the head of a Bali tourism association, who estimated that just three days of airport closures had cost the island some one trillion rupiah.

"It's a natural disaster so we can't ask it to stop."

Sarah Laight, a British hotel investor, added: “Everything is cancelled … some people are saying maybe, but then when it comes to the day they cancel, so there are no people.”

Over 60 per cent of the Balinese economy and jobs are directly or indirectly dependent on the industry.

And Bali’s “business as usual” approach until November 27th was widely regarded as highly irresponsible.

To many observers, it seemed that Bali was more interested in keeping the tourist dollars flowing than in demonstrating any duty of care to tourists.

David Beirman, senior Lecturer in Tourism at University of Technology Sydney, said: “Many of the tourists in Bali who have been inconvenienced or stranded have bitterly complained on both social and traditional media platforms.

“The most precious asset any national or local tourism board has is its reputation for honest, accurate and reliable information. 

“This includes providing warnings of potential dangers to tourists and measures that tourists can take to minimise their exposure to those dangers.”