Thousands of people rallied in front of parliament in Athens on Sunday, urging Greek Prime Minister Alexis Tsipras to resist pressure from international creditors to accept more austerity in exchange for unlocking billions of euros in bailout funds, according to Reuters. The demonstration by supporters of Tsipras's ruling Syriza party and others opposed to the euro, was the second anti-euro rally in a week in central Athens and came a day before a vital summit meeting in Brussels to try to break the deadlock that has left Greece on the brink of default. Singing, waving Greek flags and banners with slogans such as "No to the euro", "The People will not be blackmailed" and "The country's not for sale", several thousand people filled the street in front of parliament. "They want to humiliate us, why else do they insist on all these measures? We will not tolerate it any more," said 65-year-old former teacher Yiota Kananakari. With speculation over Greece's future in the euro intensifying, a counter-rally urging the country to remain in the single currency was held last week, with another scheduled to be held on Monday. Like the earlier anti-austerity and pro-euro rallies over the past week, Sunday's demonstration was far smaller than the mass protests of tens of thousands that have filled Syntagma Square in central Athens at other points during the crisis. Opinion polls show broad support for Greece remaining in the euro, but there has also been deep resentment at the cuts to pensions and wages imposed on Greece during years of recession that have left an unemployment rate of more than 25 percent. "The people have said no to the measures and the lenders must understand this, they must listen to us," said 65-year-old pensioner Fotis Mavroudis. "How can someone get by on 400 euros ($450) month, with all these taxes, with all the bills we have to pay?" After a weekend spent with close aides working out Greece's proposals to lenders, Tsipras is due to meet the heads of the European Commission, the European Central Bank and International Monetary Fund, the main creditors, before a broader meeting of euro zone leaders on Monday. Officials say he is ready to make concessions in some areas but has resisted cuts to pensions that the lenders have demanded to shore up Greece's battered public finances. Greece needs a deal to unlock bailout funds frozen during months of wrangling before a June 30 deadline when a 1.6 billion euro payment to the IMF falls due. If it fails to meet that payment, it risks losing ECB support that its banking system relies on to continue operating.