ENVIRONMENTAL activists who spent the night on two North Sea oil platforms to campaign against leaving parts of the old rigs in the sea ended their protest after more than 24 hours.

Greenpeace International said activists from the Netherlands, Germany and Denmark had boarded Shell’s Brent Alpha and Bravo platforms as part of a protest against plans by the firm to leave parts of old structures in the North Sea.

The organisation said the group of protesters scaled the platforms – which are no longer operational and lie north-east of Shetland – and hung banners reading “Shell, clean up your mess!” and “Stop Ocean Pollution”.

Greenpeace confirmed yesterday that five activists left the platforms after spending more than 24 hours on board.

It said Shell’s decommissioning plans will leave parts of four Brent oil platforms at sea with a total of around 640,000 cubic metres of oily water and 40,000 cubic metres of oily sediment containing more than 11,000 tonnes of oil.

Greenpeace International said that while a ban on dumping installations and platforms in the North East Atlantic ocean had been agreed in 1998, Shell has requested an exemption from the UK Government.

It is calling for governments to protect the ocean and “not cave into corporate pressure”.

But a Shell spokesman said on Monday that the company had spent 10 years conducting in-depth research into decommissioning the Brent platforms and its recommendations were the result of more than 300 scientific and technical studies.