WELLINGTON: Tonga was battening down Friday as a powerful tropical cyclone bears down on the Pacific island nation, officials said.

Tropical Cyclone Ian, a category four system packing winds of up to 230 kilometres per hour (143 mph), was expected to make landfall early Saturday, the UN Office for the Coordination of Humanitarian Affairs (OCHA) said.

"The cyclone may cause destructive winds, heavy rain, high swells and flash flooding in low-lying coastal areas," it said, adding that many people were boarding up windows and cutting back trees to minimise potential damage.

Red Cross emergency teams were on standby.

Tonga's National Emergency Operations Committee advised people to stock up on enough food and water to last for three days.

SOURCE: APP/AFP