A rockslide crashed onto a mountain road amid torrential rains in northern Thailand.

Footage shows boulders and uprooted trees covering Highway 1093 as heavy downpours pummeled Chiang Rai on July 14.

The road, which leads to the popular Phu Chi Fa National Park, has been closed as authorities cleared the obstruction.

Villagers and disaster response personnel used chainsaws to slice through thick tree trunks, allowing motorcycles to pass through. However, larger vehicles were still banned from using the route due to large cracks on the tarmac.

A spokesman for the Wiang Kaen district office said: 'We have asked the local highway authority to dispatch heavy machinery and remove the remaining rubble. We hope to reopen the road to traffic as soon as possible.'

The Water Resources Department had earlier issued a warning for areas around the Phu Chi Fa National Park, after the region saw 130 millimetres (five inches) of rainfall within 24 hours.

The Northern Meteorological Centre reported that northern Thailand was being lashed by heavy rains due to the combination of a low-pressure cell covering Laos and northern Vietnam, and the strong southwesterly monsoon prevailing over the Andaman Sea and the Gulf of Thailand.

Thunderstorms were expected to affect 80 per cent of northern Thailand, with heavy to very heavy rain in some provinces, including Chiang Mai, the agency said.

Thailand and neighbouring countries in Southeast Asia are at the start of their annual monsoon rainy season which sees soaring temperatures followed by powerful rain storms. The rudimentary infrastructure often struggles with the deluge, leading to widespread flash floods.