The UN Secretary-General António Guterres has expressed his deep concern after reports of a tsunami and ash affecting Tonga following the eruption of an undersea volcano near the Pacific nation.

Guterres aired his concern about the tsunami warnings that have been issued in other countries such as Australia, New Zealand, Japan and the United States.

“The United Nations offices in the Pacific are closely monitoring the situation and are on standby to provide support if requested. The Secretary-General is grateful to countries that have already offered their support”, UN spokesperson Farhan Haq said in a statement published on Saturday.

Tsunami waves crash into homes in Tonga.
Photo: Consulate of the Kingdom of Tonga

According to the Tonga Geological Services, a massive underwater volcano erupted just before sundown on Friday with plumes reaching more than 12 miles above sea level. A cloud of ash and steam reached about 150 miles across, an event captured by satellite images that have been shared by various meteorological agencies.

The United Nations Office for the Coordination of Humanitarian Affairs (OCHA) confirmed on Sunday that a tsunami waves of 1.2 metres hit the coastline and around Nuku’alofa causing yet to be detailed damage to buildings and infrastructure.

Currently, communications with Tonga are a challenge as regular phone lines are down, the internet cable from Fiji to Tonga seems to have been damaged, and satellite phones are only working intermittently.

Initial information received by the Office indicates that the main island Tongatapu, with the capital Nuku’alofa, is covered with some 2cm of ash and there is concern about water accessibility.

No injuries or deaths are currently reported but a person is allegedly missing (a member of the coast guard).

OCHA is working to establish lines of communication with Tonga’s National Emergency Management Office (NEMO) which is leading the assessment and potential response – in close cooperation with the Tonga Red Cross Society.

While in Suva, the Secretary General of the Pacific Islands Forum, Henry Puna issued a statement in Suva today pledging resources of the Forum to the government and people of Tonga.

Tonga’s Geological Services captured images of the undersea volcano spewing ash into the air before the eruption. Photo: AFP: Tonga Geological Services/Eyepress / ABC

“Like the rest of the Forum family, I am shocked by the volcanic eruptions in Tonga. Even from the relative safety of Suva, we could feel and hear the eruptions which rocked the Kingdom and large parts of the region to its core.

“I am anxious about the safety and welfare of the people of Tonga and pledge the resources of the Pacific Islands Forum to Tonga.

Puna said he will speak with Prime Minister Hu’akavameiliku Siaosi Sovaleni once communication is restored to determine how the Pacific Islands Forum can be of assistance.

“In the coming hours and days we will get a clearer picture of the situation in Tonga, as well as the rest of the Blue Pacific Continent.

“In the meantime, I ask that we keep the people and Government of Tonga in our thoughts and prayers as they respond to this once in a millennium natural disaster, said Puna.