Coast guards are preparing to siphon oil from a tanker that sank during typhoon Gaemi in the Philippines.

Footage taken on July 28 shows the Philippine Coast Guard (PCG) spraying oil dispersants into the sea off Limay town in Bataan province, where the MT Terra Nova vessel capsized amid rough weather on July 25.

The tanker had been carrying 1.4 million litres of industrial fuel, and authorities were scrambling to prevent a disastrous oil spill.

However, siphoning operations were delayed as divers had to seal several valves leaking oil.

PCG Bataan Station commander Lieutenant Commander Michael John Encina said on Monday: 'We have sealed 14 as we speak. There are still 10 left, but the leak is minimal.'

PCG spokesman Rear Admiral Armand Balilo said: 'The order is to cover and seal the valves first to ensure there are no additional leaks before starting the siphoning operations.'

He added that a 14-kilometre slick had spread from the MT Terra Nova, but said the spill was still thin and can be addressed with dispersants.

He said: 'Based on the report of Harbor Star shipping services, they saw a minimal leak from the tanker's valves. But as observed, it was not yet alarming because the flow is minimal, and the tanker itself was still intact.'

Siphoning operations were expected to start on Tuesday, July 30, and authorities said they hoped to finish in two weeks.

The MT Terra Nova sank off Bataan province typhoon Gaemi lashed the Philippines early morning on July 25. One crewman aboard died, while 16 others were rescued.

The Philippine Coast Guard is bracing to contain a major oil spill, as the vessel was reported to have been carrying 1.4 million litres of industrial fuel.

Last February, the MT Princess Empress tanker carrying 800,000 litres of industrial fuel sank and caused a disastrous oil spill in the Philippines' Oriental Mindoro province.

The spill took three months to contain, destroying swathes of coral reefs and disrupting the livelihoods of thousands of fishermen across at least six provinces.