Taiwan, the Philippines and China have issued warnings of torrential rains and destructive gusts as the year's most powerful typhoon inched closer.

With ferocious winds of 205 kilometres per hour, Super Typhoon Usagi is projected to smash into the southern Chinese coast later in the weekend.

At 03:00 GMT on Friday it was centred 1,160 kilometres southeast of Hong Kong, officials in the Chinese territory said.

"It is the strongest typhoon in the west Pacific region this year," a weather forecaster at the Taiwan Central Weather Bureau told the AFP news agency.

Philippines authorities issued a signal four alert for the Batanes island group in the extreme north of the country, warning large trees could be uprooted, plantations flattened and power and communications infrastructure down.

"Damage to affected communities can be very heavy," the Philippine Atmospheric, Geophysical and Astronomical Services Administration said.

"The situation is potentially very destructive to communities. All travel and outdoor activities should be cancelled."

The country's National Disaster Risk Reduction and Management Council said Usagi would cause intense rainfall of 10-20 millimetres per hour within a 700-kilometre range.

Hong Kong officials warned of worsening weather in the southern Chinese territory.

"Weather will deteriorate significantly with strengthening winds and rough seas," the Hong Kong observatory said. Its tropical cyclone track map showed the storm would hit the city after 8:00pm (12:00 GMT) on Sunday.

'Yellow' alert

Mainland Chinese weather authorities have issued a "yellow" alert, state media reported, the third-highest on its four-tier warning system, according to the official official Xinhua news agency.

China's State Oceanic Administration expects Usagi to hit the coast between south China's Guangxi Zhuang Autonomous Region and southeastern Fujian Province on Sunday evening.

Typoon Utor, which struck last month, killed eight people in the Philippines and left tens of thousands displaced and whole towns badly damaged when it raked across the north of the main island of Luzon.

Utor, which also led to deaths in China, forced the closure of financial markets, schools and businesses in Hong Kong, disrupting hundreds of flights and also caused the sinking of a 190-metre-long cargo ship to the city, but all 21 crew were rescued.

A super typhoon is the most intense tropical cyclone, with a maximum sustained wind speed reaching 185 kilometres per hour or above.

Source: Agencies