Greek ruling conservative New Democracy (ND) party lead in the general elections with 41.1 per cent of the votes, the first official results announced by the Interior Ministry showed.
Meanwhile, the main opposition party, the SYRIZA-Progressive Alliance, won 20 per cent of the votes, it added on Sunday.
Greeks went to the polls on Sunday to elect their representatives in the next 300-member parliament, Xinhua news agency reported.
According to the estimates, ND will secure 145 seats, falling short of an outright majority, and SYRIZA 71 seats.
With 30.3 per cent of the votes counted, five parties that passed the three per cent threshold will enter the new parliament, said the Interior Ministry.
The socialists PASOK-KINAL (Panhellenic Socialist Movement-Movement for Change) will receive 12.7 per cent of the votes, the Communist Party of Greece (KKE) 6.7 per cent, and the right-wing Elliniki Lysi (Greek Solution) 4.5 per cent, according to the estimates.
The final results will be announced on Monday. After that, Greek President Katerina Sakellaropoulou will give a mandate to the leader of the biggest party to form a new government. Under the constitution, leaders of the top three parties have three days each to form a coalition.
If all efforts fail, a caretaker government will lead Greece to a second ballot by early July. In the second ballot, a revised electoral system which provides a bonus of up to 50 extra seats for the winning party, will be used, facilitating the formation of a single-party government.
In the previous general elections in July 2019, ND had won 39.8 per cent of the vote with 158 seats in the parliament, and SYRIZA 31.5 per cent of the votes with 86 seats.