Up to 100 people have been killed and several others are missing after intense flooding struck Malaysia, Thailand and the Philippines.

Reuters reports that flash floods and mudslides have caused the deaths of at least 53 people in the central and southern Philippines.

Up to a quarter of a million people have been displaced in Malaysia, where the state of Kelantan has been the worst hit.

Volunteer William Cheah is helping relief efforts there:

"The severity and scale of the floods had taken the authorities completely by surprise as it was worse than anticipated, overwhelming all disaster management plans and preparations," Malaysian veteran opposition MP Lim Kit Siang said in a statement at the weekend.

The country's prime minister Najib Razak travelled to the worst-hit state of Kelatan on Saturday, a day after cutting short his holiday in Hawaii.

The prime minister became the focus of criticism after pictures emerged of him playing golf in Hawaii with US President Barack Obama during the storms.

Northeastern Malaysia is regularly hit by flooding during the annual monsoon, although this year torrential rains have been unusually bad.