A tropical storm travelling to the Philippines is strengthening as it approaches the country and may develop into a super typhoon.

Typhoon Mangkhut has already passed the Pacific Islands, travelling at over 100mph.

The storm will arrive in the northern part of the Philippines as its wind speed rises, PAGASA, the country's weather agency, said.

PAGASA officials warned that the storm could become a super typhoon as it intensifies. The typhoon is currently travelling with wind speeds of 125mph near its centre.

The typhoon has already felled trees and power lines in Guam, a US Western Pacific territory, forcing hundreds of people to flee to emergency shelters and schools overnight. There were no reports of casualties.

Officials warned that ​heavy rain and strong winds were possible over Luzon, the largest island in the Philippines.

Northern Luzon is sparsely populated compared to the rest of the island, with CNN reporting over three million people live in the affected region.

The surrounding sea is likely to be increasingly rough and authorities in the Philippines have instructed the public to wait for updates.

The country's president, Rodrigo Duterte, was urged by opposition groups to focus on the approaching typhoon instead of on his ongoing war of words with a fierce critic.

The Global Disaster Alert and Coordination System has said that in total 43.3 million people may be affected by the typhoon across the Philippines, China, Guam and the Northern Mariana Islands and that a high humanitarian impact is expected.

A tropical storm killed over 200 people in the Philippines last year. Storm Trembin caused landslides and flash floods and left thousands homeless in December 2017.