The Monaro Voui volcano, located on the northern island of Ambae, has been simmering for weeks and finally erupted on Tuesday, September 26.
Some 7,000 residents – roughly 70 per cent of the population of Ambae – have forced to evacuate over the last few days as the threat of an eruption grew larger.
The Vanuatu Meteorology and Geo-Hazards Department raised the alert level from three to four over the weekend as it warned of “flying rocks and volcanic gas”.
Vanuatu's National Disaster Management Office director, Shadrack Welegtabit, said: “There's ash, fire, stones and lava being thrown out from the mouth of the volcano.
“There's a lot of activity going on.”
The Meteorology and Geo-Hazards Department said that villages within a 6.5 kilometre radius of the volcano could be affected by the eruption, but warned that areas even further afield could be exposed ash falls and acid rain.
The volcano has been active since 2005, when it last erupted, but there has been a notable increase in activity over the last few weeks.
The nation of Vanuatu is made up of 80 small islands and is located between Australia and Hawaii.
Manaro Voui is not the only volcano causing trouble south of mainland Asia.
Mount Agung volcano in tourist hotspot Bali has been hit by 300 huge tremors over a six-hour period, sparking fears it could erupt for the first time in 50 years.
Officials said on Sunday morning that the volcano had not yet erupted and there did not appear to be any ash.
However, a 12km zone circling the mountain has been declared unsafe, they said.