Elon Musk's satellite internet venture is helping to restore connectivity to the Pacific Island nation of Tonga, according to an official in Fiji where the work is underway.

Tonga's sole optic-fibre link to the internet and the rest of the world was severed by a volcanic eruption on Jan 15 and only limited connectivity has been possible since.

"A SpaceX team is now in Fiji establishing a Starlink gateway station to reconnect Tonga to the world," Fiji's Attorney-General Aiyaz Sayed-Khaiyum said on Twitter.

Starlink is a division of Tesla boss Musk's SpaceX aerospace company and in January Musk himself had taken to Twitter to mention that Starlink may be able to help.

The Hunga Tonga-Hunga Ha'apai volcano eruption triggered a tsunami that destroyed villages and resorts and blanketed the capital of the nation of about 105,000 people in ash, as well as cutting the fibre-optic communications cable.

The timing of SpaceX's work is not clear, although the Fijian Broadcasting Corporation, citing Sayed-Khaiyum, said engineers would operate a ground station in Fiji for six months.

SpaceX did not immediately respond to an emailed request for comment. Tonga's prime minister's office and state telecom Tonga Communications Corporation could not immediately be reached by phone or email.

Refinitiv shipping data shows cable repair ship Reliance has been off the coast of Tonga's main island for nearly a week as it seeks to fix the damaged subsea cable.

Any improvement in communications is likely to be a relief for Tongans who have struggled to stay in touch with relatives abroad and to assist recovery efforts that have also been hampered by a COVID-19 lockdown.