Police in Paris have broken up a stunt by Greenpeace activists who dangled from a bridge and unfurled banners on the Seine River that call for cuts in nuclear power.

The activists are weighing in on a parliamentary debate this week about nuclear power in France. Greenpeace spokesman Sylvain Trottier said police detained five activists Monday.

The banners showed a picture of President Francois Hollande and his campaign-trail pledge to reduce France's dependency on nuclear power from more than two-thirds of French energy production today.

Hollande's Socialist government has promised to reduce that to 50 percent by 2025, but a Senate bill passed last week made no reference to that deadline. The National Assembly, parliament's lower house, has approved that timetable.