The environmental protection organization Greenpeace was protesting off the Wadden Sea islands of Schiermonnikoog and Borkum on Tuesday against the planned extraction of natural gas in the North Sea.
Five demonstrators climbed from rubber dinghies onto the drilling platform about 20 kilometres north of the Dutch island of Schiermonnikoog and tied themselves to its support legs, Greenpeace said on Tuesday.
Greenpeace said German and Dutch environmentalists are involved in the action. They are protesting against a planned natural gas extraction by the Dutch company One-Dyas.
A Dutch court later Tuesday suspended the controversial extraction for the time being.
The highest court in the Netherlands, the High Council, imposed a temporary halt to construction on Tuesday in The Hague.
The drilling platform may not be built or operated until a decision has been made on the application for a temporary injunction by German and Dutch environmentalists. The court intends to hear the application next week.
Sascha Müller-Kraenner, managing director of Environmental Action Germany (DUH), praised the decision. He called on the authorities in the state of Lower Saxony - to which Borkum belongs - to deny the company's application to drill in German territorial waters.
Last week, the Dutch Ministry of Economic Affairs had cleared the way for more natural gas extraction in the North Sea. The environmental licence had been amended following a court ruling.
In April, an administrative court in The Hague partially ruled in favour of plaintiffs against the drilling and confirmed a construction freeze for the drilling platform.
A number of shortcomings identified by the court were then rectified. Environmental organizations from the Netherlands and Germany are to take further legal action against drilling near the Wadden Sea nature reserve.
One-Dyas plans to extract natural gas off the two North Sea islands this year, and has set up a production platform in Dutch territorial waters.