The head of Greece's Radical Left Coalition, whose strong gains in last month's elections deepened concerns over his country's future in the European single currency, vowed Friday to cancel Greece's international bailout agreement if he wins an upcoming repeat ballot.

Alexis Tsipras, whose Syriza party came second in the inconclusive May 6 polls, said there was no way to partially implement the terms of the bailout that the heavily indebted country has come to rely on to pay its way.

Presenting his party's economic program, he said he would seek to repeal the bailout terms, which have included deep spending cuts and stiff tax hikes and have been blamed for Greece's prolonged recession.

The debt-strapped country holds its second election in six weeks on June 17. It was called after the center-right New Democracy party won the May 6 poll but without enough votes to form a government, and coalition talks collapsed.

"The first act of a government of the left, as soon as the new Parliament is sworn in, will be a cancellation of the bailout and its implementation laws," Tsipras said, as party supporters who packed an arts exhibition center to hear him speak chanted "the time of the Left has come."

The young leftwing leader — whose party is ahead in the latest pre-election opinion poll — has come under intense criticism from his political rivals, who accuse him of advocating unrealistic policies that will bankrupt the country and force it out of the 17-member eurozone and its treasured membership in the European Union's joint currency. Opinion polls have consistently shown an overwhelming majority of about 80 percent of Greeks want to remain in the euro.

"We heard today from Syriza how it will lead the country out of Europe and the euro," said New Democracy spokesman Yiannis Michelakis. "How the last businesses will collapse or leave the country."

Whether they have had New Democracy or Syriza ahead, all opinion polls since the May 6 election have shown that no party will win enough votes on June 17 to form a government on its own, and will need to form a coalition with another party.

Results of a poll published Friday — the last day before a two-week pre-election ban takes effect — showed Syriza pulling ahead, projecting it to win 31.5 percent of the vote compared to New Democracy at 25.5 percent.

The socialist PASOK party, which came to power in a landslide in 2009 elections, saw its support crumble on May 6, coming in third place with a meager 13 percent compared to ND's 18.9 and Syriza's 16.8 percent. Friday's poll projected it as performing about the same on June 17, with 13.5 percent.

Tsipras insisted his policies would not endanger Greece's euro membership, arguing that the continued implementation of the austerity measures imposed in return for billions of euros worth of rescue loans from other eurozone countries and the International Monetary Fund would be what would eventually force the country out of the currency.

"The false dilemmas of 'memorandum or drachma' are being used to hide the only true equation," he said, referring to the bailout agreement. "The memorandum equals a return to the drachma."

The bailout agreement "is a mechanism of definitive bankruptcy and pushing the country to a voluntary withdrawal from the eurozone."

The terms of the country's rescue loans would be replaced by his party's "national recovery plan" which will focus on development and "fair fiscal consolidation," Tsipras said.

This will include canceling a law that cut the minimum wage by 22 percent and by 32 percent for young people up to the age of 25. The plan will restore the minimum monthly wage to €751 euros and unemployment benefit to €461.5 euros, while also extending eligibility from one year to two.

His plan also includes reducing consumer tax, which has increased to 23 percent, especially on basic food items and the tourist industry, and freezing or overturning privatizations — including for the Hellenic Telecoms company OTE and the Public Power Corporation.

Tsipras also pledged to nationalize banks that are being recapitalized. The plan seeks to cancel extra taxes imposed for those on middle and low incomes, as well as for the unemployed, those on low pensions and people living on the poverty line.

Funding for state income would come from taxing wealth and high incomes through a "radical reform of the tax system".

Tsipras predicted that under the bailout terms, Greece would be unable to return to the markets, from which it has been blocked out since mid-2010 by sky-high borrowing rates, during this decade.

"There is no more or less bad memorandum," he said, referring to the bailout agreement. "You either implement the memorandum, or you cancel it. ... We will cancel it."

Tsipras said that if he wins enough votes to form a leftwing government, he will "seek a Europe-wide deal to drastically reduce the debt payments, or seek a debt moratorium."

Friday's opinion poll, commissioned by Kathimerini newspaper and Skai television, was carried out by Public Issue on May 25-30. The company questioned 1,210 people and the poll had a margin of error of plus or minus 3.2 percent.