Samaras was tasked with building a government by President Karolos Papoulias on Monday. The New Democracy party chief said he would meet with leaders of all parties that "believe in Greece's European orientation and the euro" later in the day.

"I will try to form a long-term national unity government," Samaras said, adding that he was optimistic about the outcome.

New Democracy won 129 of the 300 parliamentary seats in Sunday's elections. With backing from the socialist Pasok party, Samaras would control 162 seats.

The two parties have governed Greece in turns for decades. They were part of a national unity government last year that lasted only six months. That government was dissolved in April.

Elections last month were inconclusive as no party was able to form a majority, forcing Sunday's second try.

A new mandate

New Democracy campaigned on a platform of keeping Greece within the eurozone. There were fears heading into the election that if the radical leftist Syriza party came to power, it would be the end of the euro in Greece. The party had claimed to be adamantly against the harsh conditions of the bailout deal.

"In any case," Syriza's leader Alexis Tsipras said after the vote, "everyone should know that the austerity measures and the measures to sell public wealth cannot be implemented since they are deprived of legitimacy."

Syriza has refused to enter a coalition with parties in favor of the international bailouts and the attached austerity measures.

New Democracy's Samaras said he hopes to amend some of the terms of the bailouts so "the Greek people can escape from today's torturous reality."

Cautious support from abroad.

EU leaders have acknowledged that Greece desperately needs to create jobs and stimulate its economy but have not agreed to fundamental changes of the bailout deal.

German Chancellor Angela Merkel was one of the first to make a congratulatory phone call to Samaras on Sunday. A government statement said the chancellor told Samaras that "she would work on the basis that Greece will meet its European commitments."

Guido Westerwelle, Germany's foreign minister, told reporters in Berlin that he was relieved by the results and that it was "a vote for Europe."

However, he added, "there are no concessions, because what has been agreed is now what we will implement … There can be no substantial changes to the agreement."

In a statement issued from Mexico the day before a Group of 20 summit, European Council President Herman Van Rompuy issued a statement along with European Commission President Jose Manuel Barroso.

"We will continue to stand by Greece as a member of the EU family and of the euro area," they said.

mz/ncy (AFP, AP, dpa)