Thais have been warned not to travel to northern Bali after Indonesia authorities raised Mount Agung's alert status to the highest level on Friday.
The Thai Embassy in Jakarta posted on Facebook on Saturday, urging Thais to avoid travelling to the area and to closely follow news from Indonesian authorities.
The warning followed reports of a “tremendous increase” in seismic activity. It last erupted in 1963, killing 1,100 people.
AP reported from Bali on Saturday Indonesia’s National Disaster Mitigation Agency said no one should be within 9km of the crater and within 12km to the north, northeast, southeast and south-southwest where lava flows or rapidly moving white-hot ash clouds from an eruption could reach.
Waskita Sutadewa, spokesman for the disaster mitigation agency in Karangasem district around Mount Agung, has said nearly 11,300 villagers have been officially evacuated.
He said the real number of displaced might be two or three times that, since many have voluntarily fled their homes.
Officials have said there is no current danger to people in other parts of Bali, a popular tourist island famous for its surfing, beaches and elegant Hindu culture.
In its last eruption in 1963, the 3,031m Agung hurled ash as high as 10km and remained active for about a year.
The mountain, 72km to the northeast of the tourist hotspot of Kuta, is among more than 120 active volcanoes in Indonesia.
The country of thousands of islands is prone to seismic upheaval due to its location on the Pacific “Ring of Fire”, an arc of volcanoes and fault lines encircling the Pacific Basin.