DAKAR (Reuters) - Former Ivory Coast Prime Minister Guillaume Soro, a leading candidate barred from standing against President Alassane Ouattara in an election next month, called on Thursday for the opposition to block Outtara’s re-election by any lawful means. The opposition says Ouattara is violating the constitution by seeking a third term; the president says a constitutional change means his two-term limit has been reset. At least a dozen people have been killed since anti-Ouattara riots broke out last month, tilling up memories of 2010-11, when 3,000 people died in a civil war sparked by a disputed election. In his first public comments since he was barred from standing, Soro, prime minister from 2007-2012 and head of parliament until last year, said a third Ouattara term would amount to a “civilian coup d’etat”. Speaking to reporters in Paris, where he has fled to escape corruption charges he says are politically motivated, he said: “I call for unity of action by the opposition to stop Mr Ouattara ... by all legal and legitimate means.” He said the people did not want an election in its current form, adding, without elaborating: “There will be no election.” The Constitutional Council, a judicial body, whittled down an initial list of 44 presidential candidates to just four this week. It approved Ouattara’s candidacy but ruled out former President Laurent Gbagbo, who was acquitted by the International Criminal Court for crimes against humanity charges last year, as well as Soro.