A 7.2 magnitude earthquake struck 40 km (25 miles) west of Vanuatu's town of Port-Olry, the United States Geological Survey said on Sunday.
The earthquake was at a depth of 10 km, USGS said.
"Tsunami waves reaching 0.3 to 1 meter above the tide level are possible for some coasts of Vanuatu," said the Pacific Tsunami Warning Center.