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

Alexis Tsipras, whose party came second in the inconclusive May 6 polls, said there was no way to partially implement the terms of the bailout.

Presenting his Syriza 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 a 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.

The young leftwing leader 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 its treasured membership in the European Union's joint currency. Opinion polls have consistently shown an overwhelming majority of about 80 per cent of Greeks want to remain in the euro.

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 per cent for young people up to the age of 25. The plan will restore the minimum monthly wage to (EURO)751 euros and unemployment benefit to (EURO)461.5 euros, while also extending eligibility from one year to two.

His plan also includes reducing consumer tax, which has increased to 23 per cent, especially on basic food items, and freezing privatizations.

The plan also 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.

Tsipras said he would fund state income by taxing wealth and high incomes through a "radical reform of the tax system".

Tsipras' Syriza party has been neck-and-neck with New Democracy in most recent opinion polls. 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 per cent compared to ND's 18.9 and Syriza's 16.8 per cent.

He 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."