ANKARA - Turkish President Tayyip Erdogan said on Monday no party had won a mandate to govern alone in a parliamentary election and urged all political parties to work towards preserving an environment of confidence and stability in the country. 'Our nation's opinion is above everything else,' Erdogan said in a statement released by his office, his first public comments on Sunday's vote. 'I believe the results, which do not give the opportunity to any party to form a single-party government, will be assessed healthily and realistically by every party.' Erdogan's hopes of assuming executive powers suffered a major setback on Sunday when the ruling AK Party he founded failed to win an outright majority for the first time.