By Renee Maltezou and Angeliki Koutantou
ATHENS (Reuters) - Greece's two main opposition parties on Tuesday turned down mandates offered to them to form a coalition government, setting the stage for a second election in June after an inconclusive vote on May 21.
Leftist Syriza leader Alexis Tsipras and Socialist PASOK head Nikos Androulakis handed back mandates offered to them separately by President Katerina Sakellaropoulou.
Prime Minister Kyriakos Mitsotakis, whose New Democracy party won 40.8% of the vote on Sunday compared with Syriza's 20.1%, had earlier opted against forming a coalition and has pushed for a second vote in a bid for an outright majority.
Tsipras said he could not form a coalition, after many voters turned away from Syriza's radical, anti-establishment style that had swept it to power during the turbulent years of the Greek debt crisis.
"I have no reason to hide that the electoral result is a painful shock, it was unexpected," Tsipras, whose Syriza ruled from 2015 to 2019, said outside the presidential mansion.
"I take full responsibility for this result, but in my dictionary that means standing and fighting."
A second vote is tentatively scheduled for June 25, when a system of bonus votes for the winning party comes into play that could hand New Democracy a majority in parliament to govern alone.
Opposition parties do not have enough seats to form a ruling alliance without involving New Democracy.
Sakellaropoulou, the Greek president, will now appoint a caretaker government.
"Based on the public verdict, there is no room for convergences of our (political) platforms which is why I am returning this exploratory mandate immediately," PASOK's Androulakis said during a meeting with the Greek president.
Before the election, Mitsotakis told Reuters he wanted to ensure his party secured a comfortable majority, saying one-party administrations were more stable than a coalition.
The defeat of Syriza, which has called the second vote a "final battle", has revealed a split in the Greek left. Two small leftist parties, set up by former Syriza members, did not secure enough votes to make it into parliament.
Under electoral rules, the winner of a second vote following an inconclusive first election receives 20 bonus seats in parliament if they get 25% of the vote, and up to 50 bonus seats if they get about 40%. If Mitsotakis secured 40% of the vote again or even a little less, he would still have a majority.
To benefit from bonus seats, New Democracy needs to stay the biggest party, but that seems likely given its nearest rival Syriza secured just a fifth of votes on May 21. The total seats Mitsotakis secures will, however, depend on how many other parties make it into parliament.