Magnitude 7.3 earthquake strikes near Vanuatu

A magnitude 7.3 earthquake has struck off the coast of Vanuatu.

The quake was registered about 20 kilometres from the coast of Vanuatu's capital Port Vila about 12.47pm (AEDT).

There is no tsunami threat to Australia, the Bureau of Meteorology confirmed.

Footage posted to social media appeared to show damage to the outside of the US Embassy in Port Vila. 

Another video appearing to be from the aftermath of the quake showed several cars crushed underneath a collapsed building.

The extent of the damage is not yet known, but it is believed that some people may be trapped under collapsed buildings.

Early data from the United States Geological Survey indicates the quake was registered at a depth of 57 kilometres.

The jolt was followed by a magnitude 5.5 aftershock at the same location.

Vanuatu government websites were offline in the aftermath of the quake and phone numbers for the police and other public agencies did not connect.

The USGS warned of tsunami waves for some coasts on Vanuatu, a group of 80 islands that is home to about 330,000 people. Waves could reach 0.3 metres to 1 metre above the tide level, the agency said.

Some islands in the low-lying atoll nation are 3 feet above sea level.

The USGS also warned of tsunami waves registering less than 0.3 metres above the tide level for a number of nearby Pacific islands including Papua New Guinea, Fiji and the Solomon Islands.

An update from SmartTraveller warned Australians in the area to move to high ground.

Australians are also advised to monitor local media for emergency updates and follow the advice of local authorities.