Magnitude-7.1 earthquake hits Tonga, tsunami threat cancelled

A magnitude-7.1 earthquake has hit near Tonga, prompting authorities to issue a tsunami warning for the Pacific island country.

The US Tsunami Warning Centre has since cancelled its tsunami advisory, saying the threat had now passed.

It said small fluctuations in wave height were detected at two buoys in the area.

It had earlier warned tsunami waves were possible for coasts located within 300 kilometres of the earthquake epicentre.

Geoscience Australia said the quake struck about 100 kilometres north-east of Tonga.

The US Geological Survey says it hit at a depth of 10 kilometres.

In a statement on social media, the Tonga Meteorological Service urged residents to either move to higher ground, further inland, or to the third floor of a reinforced concrete building.

It said a tsunami warning was now in force for the island nation.

New Zealand's tsunami buoys off Tonga showed a brief 70cm increase in water height.

The Joint Australian Tsunami Warning Centre says there is currently no threat to the Australian mainland.

Tonga is made up of 171 islands and is more than 3,500 kilometres off of Australia's east coast.