The World Meteorological Organization (WMO) said Tuesday that volcanic activity at Mount Agung in Bali, Indonesia, and potential risks to air transport from volcanic ash were being closely monitored.
"Indonesian authorities have been closely watching Mt. Agung for weeks," WHO media officer Clare Nullis said at a UN briefing in Geneva.
A continuous volcanic eruption has been observed at Mount Agung since Nov. 25, said WMO.
The height of the eruption has been steadily increasing, ash is currently observed to a height of around 7,620 meters, and a small amount of ash has fallen at Denpasar Airport and across Bali's southeast.
"Denpasar's airport remains closed for a second day on Tuesday and eruptions and ash falls are likely to continue...Volcanic ash clouds pose a significant hazard to aviation operations," said Nullis.
She noted that on the previous day, the National Board for Disaster Management in Indonesia raised the alert level to level four and urged people living within 10 km of the volcano to evacuate.
She explained that information on volcanic ash clouds played an important role in helping meteorological watch offices, civil aviation authorities, airlines and other organizations to avoid aircraft-related disasters.