ST. PETERSBURG, December 7 (RIA Novosti) - Greenpeace activists attempted to stop a Russian ship carrying depleted uranium on its approach to St. Petersburg, the press service of Greenpeace's office in the city said Wednesday.

The attempt to block the Kapitan Kuroptev, loaded with 450 metric tons of depleted uranium from France, was made at 3.15 p.m. GMT near Kronstadt.

"Three boats with 11 activists on board tried to stand in the ship's way, burning signal lights and putting buoys warning of a floating radiation hazard. However, the ship picked up speed and used water cannons, and is now on its way to the port," a spokesman for the press service said.

Greenpeace's office in St. Petersburg is not planning any action after the ship arrives at the port. "Nevertheless, we intend to continue to attract the public's attention to the problem in the future," the source said.

On Thursday, French police detained some 20 Greenpeace activists from France, Austria and Russia attempting to prevent the loading of the French cargo onto the Kapitan Kuroptev, a French radio station reported.