Greeks will head to the polls for a second time after the three main party leaders rejected a mandate by Greek President Katerina Sakellaropoulou to form a coalition government, following Sunday's inconclusive vote.

Prime Minister Kyriakos Mitsotakis turned down the mandate on Monday after his ruling New Democracy party scored a big win on Sunday but fell just short of an outright majority. Mitsotakis said that he would seek a second vote on June 25 to secure that majority.

Leader of center-left Syriza party Alexis Tsipras and the leader of socialist party PASOK Nikos Androulakis also rejected the mandate.

President Sakellaropoulou is expected to appoint judge Ioannis Sarmas as a caretaker prime minister this afternoon to prepare the country for new election, according to a statement by the presidency.

Although the date has not been formally announced yet, Mitsotakis has stated that if there are no constitutional issues, the repeat election will happen on June 25.

This is a breaking news story. More to follow.