ATHENS - Greek conservative parties the New Democracy (ND) and the Democratic Alliance announced on Monday that they will join forces ahead of the critical June 17 national polls, the second in two months, that could determine the debt-ridden country's economic future and stay in the eurozone.

Following the inconclusive May 6 general elections that gave no party absolute parliamentary majority and the parties' failure to broker a deal on a coalition government, political forces seek alliances ahead of the new polls.

Antonis Samaras as leader of the ND party that topped the May 6 polls with some 19 percent of votes, attempts to build a wide center-right alliance on a pro-European, pro-reform agenda to compete against left anti-bailout parties that have increased their percentages riding on the wave of disillusionment of recession-hit Greeks.

"We must not leave populism forces prevail in the country," said Samaras, sealing the agreement with a handshake with Democratic Alliance chief Dora Bakoyianni.

"It is time to put differences aside, political and personal, for the sake of Greece to create a strong, pro-European front against populism," added Bakoyianni.

The former foreign minister founded the Democratic Alliance after losing the contest for ND's leadership to Samaras and voting in favor of the first bailout agreement two years ago against party line.

The Democratic Alliance didn't win the needed three percent threshold to enter the parliament that was elected in the previous elections and dissolved on Saturday to open the way to the ballots. But the party base could give ND's percentages a significant boost in the June 17 polls, local political analysts and media commentators noted.

The radical Left Coalition (SYRIZA) that ranked second in the previous electoral battle with some 17 percent of votes, on the other hand, seeks to forge similar alliances with centre-left parties that have not made it into the parliament.

The two parties vie for the top post and an opportunity to form a viable coalition government, after the June 17 elections, if they fail to win clear parliamentary majority again, according to the latest opinion surveys.

ND argues for a renegotiation of part of the harsh austerity terms of the two bailout deals clinched with international EU and International Monetary Fund (IMF) lenders. The aim is to ease the burden off the shoulders of Greek people, securing the future flow of vital multi-billion euro loans to avoid a disorderly Greek default and possible exit from the eurozone.

SYRIZA suggests a more hard line in the dialogue with creditors that has raised concern over the reactions of EU counterparts and IMF.

Despite the party's reassurances that strongly supports Greece's membership in the EU and the eurozone, some anti-bailout statements have fuelled scenarios of political instability and a possible Greek bankruptcy and exit from the European common currency zone that could rock the international financial system.

Ahead of Wednesday's EU summit in Brussels, in the meantime, caretaker Prime Minister Panayiotis Pikrammenos, a senior judge appointed to the post last week, held throughout Monday a series of meetings with leaders of some dozen parties to discuss the country's strategy in the upcoming summit and the course to the ballots.

"A lot of useful proposals were laid out on the table regarding the summit," said a press statement released by his office at the end of the dialogue.

In remarks made to media after the talks, many party leaders called for the issuance of euro-bonds to fund development in Greece and across the eurozone. The idea has been raised by many sides from the early stages of the Greek debt crisis that erupted in late 2009, but still meets the strong opposition of Germany that fears a rise in its borrowing cost.

The press release from the interim prime minister's office added that all parties also agreed on the need to keep the cost of the new elections as low as possible. According to estimates of the Interior Ministry the May 6 polls cost about 50 million euros ($63.9 million).