“Representatives from relevant bureaus and departments also reported their preparatory work and contingency plans, particularly on measures in the prevention and handling of flooding, backflow of seawater and emergency plans for high-risk locations,” a government statement read.

Mangkhut, named after the Thai word for the mangosteen fruit, was forecast to come within 80km of the city on Sunday, but the Hong Kong Observatory said it was too early to predict a direct hit.

“It could be very close to Hong Kong,” senior scientific officer Queenie Lam Ching-chi said. “It has a large circulation with intense winds, so even if it is not a direct hit … it can constitute a great danger to Hong Kong.”

On Wednesday night, Mangkhut, the most powerful typhoon to threaten the Philippines this year, was about 1,100km (684 miles) east of Virac in the country’s north, churning across the Pacific at a speed of 22km/h (14mph) with a rainband 900km (559 miles) wide and packing winds of more than 200km/h (124mph)

Mangkhut was expected to hit the northern Cagayan province on Saturday, but officials were already ordering the evacuation of thousands of people, as well as the closure of schools, offices and businesses.

“I’m stressing that this one is very different. This is more complicated because of possible storm surges,” Cagayan governor Manuel Mamba said, as nervous residents recalled another super typhoon in 2016h that caused massive destruction.

Northern coastal and island villages in Mangkhut’s projected path would begin evacuating residents on Thursday ahead of the expected onslaught, Mamba said.

The storm was arriving at the start of the rice and corn harvest season in Cagayan, a major agricultural producer, and farmers were scrambling to save what they could of their crops, he said.

A missile test aboard a navy ship to be attended by President Rodrigo Duterte off northwestern Bataan province was cancelled due to the approaching typhoon.

The Philippines was expecting Mangkhut to be as strong as Super Typhoon Haiyan, which left more than 6,300 dead in 2013.

In Taiwan, meteorologists were expecting Mangkhut to lash the southern and southeastern parts of the island as early as Friday night.

Taiwanese premier William Lai Ching-te instructed local governments to activate their crisis management systems and be prepared for a battering.

Forced evacuations would be conducted in the event of serious flooding and landslides, cabinet spokeswoman Kolas Yotaka said.

The government would take precautions to avoid loss of life and property, especially after the devastation last week in western Japan brought by Typhoon Jebi.

The Hong Kong Airport Authority said it would closely monitor Mangkhut’s path and keep in close contact with the Observatory, the Civil Aviation Department and others to prepare for the possible impact on the operation of the airport.

The authority also sought to assure the public there would be no repeat of the Kansai chaos.

“The Hong Kong International Airport was built and designed according to the relevant government standards and guidelines,” a spokesman said. “Consideration has been given to the geography, and the risks of flooding due to extreme tidal range, and other adverse situations.”

Local carriers Cathay Pacific Airways, Cathay Dragon, Hong Kong Airlines and HK Express announced they would waive rebooking or re-routing charges if the super typhoon forced the cancellation of flights.

Cathay Pacific and Cathay Dragon said tickets issued worldwide on or before Tuesday would be eligible for the rebooking and re-routing fee waivers.

Hong Kong Airlines had a similar arrangement in place for flights between September 16 and September 18, while HK Express said it would waive fees for rescheduled flights on the same routes, but would charge the fare difference if the routes changed.

The city’s Development Bureau issued a notice to government contractors, asking them to “keep up vigilance against the threat of inclement weather impinging on the safety and normal operation of your construction sites and on public safety”, and have their emergency teams ready.

The China Railway Guangzhou Group announced the suspension of ticket sales for high-speed trains between Guangzhou and Hong Kong, as well as services between Guangzhou and Hangzhou for next Monday and Tuesday.

The MTR Corporation said in the event of a No 8 typhoon warning signal this weekend, station ticketing services at the West Kowloon high-speed rail terminus would be suspended, but online and telephone bookings would be unaffected.

Additional reporting by Bloomberg and Associated Press