Kyriakos Mitsotakis sworn in as Greece's new PM

Centre-right candidate Kyriakos Mitsotakis was sworn-in as the new prime minister of Greece on Monday, a day after his New Democracy party won a landslide victory in the country's parliamentary elections, putting an end to the rule of leftist Syriza government.

Citing official results, Al Jazeera reported that the New Democracy gaining 39.85 per cent of the vote in the Sunday's snap election, compared with 31.53 per cent for Syriza, led by outgoing Prime Minister Alexis Tsipras.

Mitsotakis, 51, arrived at the presidential palace for the official swearing-in ceremony accompanied by his wife and three children.

He then headed to the prime minister's office for a handover of duties and was expected to name his cabinet later in the day.

In his victory speech on Sunday evening, Mitsotakis vowed that Greece will "proudly" enter a post-bailout era of "jobs, security and growth".

"A painful cycle has closed," the 51-year-old said in a televised address, adding that Greece would "proudly raise its head again" on his watch.

The election results announced an outright majority to the New Democracy party with 158 seats in the 300-member Greek parliament.

"I asked for a strong mandate to change Greece. You offered it generously," Mitsotakis was quoted as saying in his victory speech.

"From today, a difficult but beautiful fight begins," he added.

Meanwhile, Tsipras, on his part, said that his party's loss was "anything but a strategic defeat" following an election showing that was much stronger than expected.

"I can assure the Greek people that from the benches of the opposition we will be present to protect the interests of people of toil and creativity," he said, after calling Mitsotakis to congratulate him on his victory.

Mitsotakis, the son of a former prime minister, had campaigned on the promise of further reforms with a focus on fewer taxes, attracting investment and improving the job market.

The election came as Greece struggles to emerge from a nearly decade-long financial crisis that saw its economy plunge by a quarter and thousands of mostly young people head abroad seeking better economic opportunities.