Norway's ruling Labour party provoked outrage from environmentalists as well as coalition members Thursday after it opened the way for oil exploration near the scenic archipelago of Lofoten.

The committee charged with outlining the party's political programme late Wednesday came out in favour of an "impact study" that would assess the effects of oil production around the islands, where most people rely on the fishing and tourism sectors.

The move could prove controversial in Norway's parliamentary elections, set to be held in September.

Environmentalists claim past impact studies have always resulted in oil prospecting.

The issue illustrates the tension between the oil industry and the fishing sector, both important sources of revenue for the country.

The waters of Lofoten hold around 1.3 billion barrels of oil equivalent, according to the Norwegian Petroleum Directorate -- but they are also the spawning ground of the largest cod population in the world.

The Labour party committee's decision, which has yet to be approved at the Labour party's April congress, was roundly criticised by NGOs.

"The turnaround of the Labour party is sad for such a fantastic food-producing area. But this is not a lost cause," said Frederic Hauge, president of the Bellona Foundation.

The issue also appeared to cause some friction within Labour Prime Minister Jens Stoltenberg's coalition government, which also includes the agrarian Centre party and the Socialist Left party.

The latter is strongly opposed to oil production in the area, saying it "will not drop Lofoten", and that it was confident that a coalition agreement blocking oil exploitation in the region could be renewed.

The latest polls show that the elections could be difficult for the centre-left government. However, the opposition is currently also divided over the issue.