A left-wing party that opposes Greece's international bailout agreements has extended its lead ahead of next month's election, according to a new poll published Friday.

The poll gave the Syriza party 30 percent support, widening its lead over the center-right New Democracy party from 2 to 4 percentage points from a poll on May 19.

The June 17 election was called after the country's political parties failed to reach a power-sharing deal after a May 6 vote that left no group with a parliamentary majority.

Greece's economy is being kept afloat on international loans, and the previous governments imposed severe spending cuts and other austerity measures that have infuriated the public. Syriza wants to scrap the loan agreements, but that has raised fears that Greece will leave the eurozone and destabilize world markets.

"There's one real choice in these elections: The bailout or your dignity," Syriza's 37-year-old leader Alexis Tsipras said at his opening campaign rally on Thursday.

"We want all the peoples of Europe to hear us, and we want their leaders to hear us when we say that no (country) chooses to become servile, to lose their dignity or commit suicide ... We are the political party that with the help of the people will fulfill our campaign promises and cancel this bankrupt bailout deal."

The Public Issue poll published Friday surveyed 1,214 people for the Kathimerini newspaper and had a 3.2 percentage point margin of error.

Shares on the Athens Stock Exchange suffered fresh losses Friday, dropping 3.45 percent to 485.18 to hit another 22-year low, as investors appeared unconvinced by a pledge by European leaders this week to keep Greece in the euro.