The Belgian army is on alert after reports that an oil slick from a sunken cargo ship in the English Channel may wash up on its beaches within hours.

Hundreds of oil-covered birds have been washed ashore over the past two days.

We have to keep the sludge out Paul Breyne provincial governor

The country has ordered 120 military personnel to be ready to tackle the slick which is reported to be 150 metres (492 feet) wide and four kilometres (2.5 miles) long.

It is expected to hit between Zeebrugge and Ostend.

"We need to protect our nature reserves - we have to keep the sludge out," Paul Breyne, governor of West Flanders Province, said as he drafted plans for floating buffers along the 66-km (40-mile) coast.

	:	Graphic guide
The Tricolor shipwreck

Bad weather has prevented two Belgian anti-pollution ships sent to the area where the Tricolor sank from pumping the oil out of the water.

One has reportedly already returned to port.

French officials say the slick formed when a salvage tug hit a fuel tank on the partially submerged Tricolor on Wednesday.

Shipping hazard

14 Dec: Tricolor and Kariba collide in heavy fog, sinking the former 15 Dec: cargo ship NSD Provider comes within 500 m of wreck 16 Dec: freighter Nicola runs into swamped ship 1 Jan: so too does fuel tanker Vicky

The Tricolor has been a shipping hazard since it collided with another vessel and sank on 14 December.

It was carrying 2,000 tonnes of fuel when it went over on its side with more than 2,850 new BMW, Volvo and Saab cars.

The head of the regional bird protection agency, Jan Rodts, said that the seabirds washed up represented only a fraction of the wildlife damaged.

"Ten percent washes ashore, 90% dies at sea," he said.

"This is only the tip of the iceberg."