The Northern Mariana Islands banned all travellers from China and declared a "state of significant emergency" Thursday, as Pacific island states stepped up measures to protect against the coronavirus outbreak.

Although Chinese tourist traffic is a pillar of the economy in the US Pacific commonwealth, Northern Mariana governor Ralph Torres said the new coronavirus "poses a significant and imminent threat".

In China, where the epidemic originated, 170 have died with thousands more infected.

Although no suspected cases of the virus have been recorded in the Northern Marianas, Torres said the risk remained "substantial" due to incubation times.

"I find that the public health threat of a traveller from mainland China carrying the coronavirus is significant and cannot be understated," he said.

"The Commonwealth Ports Authority shall communicate with all airlines with travellers directly and indirectly from mainland China to suspend the arrival of travellers for the period of this emergency declaration."

Because of the impact the emergency declaration will have on the economy, Torres said he had also ordered an immediate cost-impact analysis on the annual budget.

Several Pacific territories have taken steps to restrict access, despite being heavily reliant on Chinese tourism revenues
Several Pacific territories have taken steps to restrict access, despite being heavily reliant on Chinese tourism revenues AFP / SEBASTIEN BLANC

The Northern Mariana Islands are a self-governing chain of islands that has the US president as head of state.

The Marshall Islands and Palau, other Pacific territories with heavy visitor traffic from China, have also taken steps to restrict access.

Anyone from China, or who has transited through China, must spend at least 14 days in a country not affected by the new coronavirus before they can enter the Marshall Islands.

"In the event a traveller arrives in the Marshall Islands within the 14-day period, entry will be denied," Health Secretary Jack Niedenthal said.

Palau, which last year received more than 30,000 tourists from China, its main market, is suspending all flights from mainland China, Hong Kong and Macau from Saturday despite the economic impact.

"The government wishes it doesn't have to take this measure because Palau relies on tourism," Palau vice president and head of their national emergency committee, Raynold Oilouch, said.

"Unfortunately, by taking this measure it will have an impact on Palau's tourism. It wasn't an easy decision but a necessary one."

Papua New Guinea on Wednesday banned all air and sea travellers arriving from Asia.

Coronavirus China