Bare-chested Femen activists interrupted France's National Front president Marine Le Pen and used a bullhorn to drown out a speech by her in Paris.

Two Femen activists barged into a wreath-laying ceremony by the daughter of the party's founder, Jean Marie Le Pen.

The chaotic May Day events reflected a party in turmoil over a family feud between its 86-year-old founder and his daughter, who has pushed him to the sidelines.

During Marine Le Pen's speech at the Paris Opera House, three Femen members appeared on a nearby balcony, unfurling a flag reading "Heil Le Pen" and, using a bullhorn, briefly drowned out her speech decrying immigration and the European Union.