Cyclone Winston hits Fiji's main island Viti Levu

The most powerful storm to hit Fiji has made landfall on the Pacific nation's main island, Viti Levu.

Cyclone Winston brought winds of over 320 kph (200 mph), torrential rain and waves of up to 12m (40ft).

Flights have been cancelled, evacuation centres activated and a nationwide curfew put in place.

The category five storm - the highest level - is expected to move westwards over the main island overnight Saturday and into Sunday morning.

Before it landed, Prime Minister Frank Bainimarama warned that Fiji was facing "an ordeal of the most grievous kind".

"We must stick together as a people and look after each other. Be alert and be prepared," he said.

Cyclone Winston has already brushed some of Fiji's smaller islands, but the extent of the damage is unclear.

Cyclone Winston has brought winds, rain and storm surges

Cyclone Winston is category five - the highest storm category

Assessment teams are being sent to the affected areas, the Fiji Times reported.

The Fijian capital Suva is likely to be spared the full forces of the storm but tourist resorts are close to the cyclone's centre.

About 900,000 people live on Fiji.