Sydney, March 1 (IANS): An oil spill from a cargo ship that ran aground in the Solomon Islands has sparked fears of an environmental disaster in the Pacific, threatening a nearby world heritage site which is also home to one of the largest raised coral atolls in the world.

The bulk carrier, Solomon Trader, which was carrying 700 tonnes of heavy fuel oil and a cargo of bauxite, remained aground on Friday, over three weeks after it got stuck in the Kangava Bay on the island and caused the leakage, reports Efe news.

The ship went aground on February 5 on the remote island of Rennell during the passage of cyclone Oma, a storm system which lingered over the region for weeks.

"The oil spans 5 to 6 km across the shore and is moving towards the adjacent world heritage area," a statement from Australia's Foreign Affairs Department said.

Australia assists the government of Solomon Islands in the South Pacific in responding to emergencies.

Indonesian firm Bintan Mining Solomon Islands Limited, which hired the 225 metre-long ship registered in Hong Kong, has refused to assume liability for the accident.

East Rennell was declared a Unesco World Heritage site in 1998. It was included in the list of World Heritage in Danger due to the excessive felling of trees.

The remote region, which has featured in the eco-tourism circuit, occupies one-third of the 216,000 acre area of the island of Rennell, the southernmost territory of the Solomon Islands, and encapsulates Tegano - the biggest lake in the Pacific islands.

The lake houses many limestone islands and native species such as sea snakes.

East Rennell is also covered by dense forests with up to 20-metre tall foliage and possesses more than one thousand species, many of them endemic, of bats, birds, snails and insects apart from being home to a huge variety of flora.