The Philippines and Taiwan hunkered down on Monday as Super Typhoon Ragasa delivered punishing winds and intense rainfall while lumbering east towards an eventual collision with southern China.

The storm intensified further as it moved northwest and was expected to make landfall on the sparsely populated Batanes or Babuyan islands by early afternoon, the Philippine weather agency said.

Maximum sustained winds were 205 kilometres per hour at the storm's centre as of 11 pm on Sunday, with gusts reaching up to 250 kph as it moved toward the archipelago nation, the weather service said.

The Philippine government closed offices and schools on Monday in Metro Manila and across 29 provinces.

Local officials "must waste no time in moving families out of danger zones", interior department Secretary Jonvic Remulla said in a statement.

In Taiwan, authorities said nearly 300 people will be evacuated from Hualien County in the east, adding that figures could change depending on the typhoon's movement.

Philippine weather specialist John Grender Almario told a Sunday press briefing that "severe flooding and landslides" were expected in northern areas of main island Luzon.

"We expect that the effects of the super typhoon will be felt beginning tonight," he said. "The strongest (effects) will be at 8 am tomorrow."

Strong winds and heavy rain are likely in other areas of Luzon, although Manila, where thousands turned out Sunday to protest against fraudulent flood control projects, was expected to be largely spared.

The growing corruption scandal, involving billions of dollars lost to incomplete or "ghost" flood control projects, has seen multiple lawmakers implicated and sparked national outrage.

The Philippines is the first major landmass facing the Pacific cyclone belt, and the archipelago is hit by an average of 20 storms and typhoons each year, putting millions of people in disaster-prone areas in a state of constant poverty.

On Sunday, the Hong Kong Observatory said weather in the financial hub would "deteriorate gradually" on Tuesday and Wednesday, with gale-force winds and storm surge-driven sea levels similar to those seen in 2018's powerful Typhoon Mangkhut. (AFP)