A super typhoon sweeping towards the Philippines on Saturday was intensifying and could have a "potentially catastrophic" impact, the state weather forecaster warned, with millions of people at risk from storm surges.

A quarter of a million people have fled their homes as Super Typhoon Man-yi bears down on the Philippines. It will be the sixth major storm to hit the country in the past month, with lethal storm surges predicted.

The Philippines evacuated tens of thousands of people from their homes and cancelled dozens of flights on Saturday, as a super typhoon threatened to unleash heavy rains and powerful winds that could trigger floods and storm surges.