Police officers stand by after Greenpeace activists unveiled a banner on the Eiffel Tower. Pics/AFP

Paris's police chief called emergency talks on security ahead of a French presidential election after a dozen Greenpeace activists scaled the north face of the Eiffel Tower in broad daylight on Friday and unfurled a political banner carrying the French national motto, "Liberte, Egalite, Fraternite" (Liberty, Equality, Fraternity), with #Resist as a clear opposition to Marine Le Pen.