Thousands of protesters took to the streets of Athens on Sunday as Greece's parliament prepared to vote on a controversial tax and pensions overhaul which has sparked mass opposition.
Police said almost 15,000 people turned out to march in Athens and the second city of Thessaloniki against the measures demanded by the EU and IMF that the government is seeking to adopt ahead of a crunch meeting of eurozone creditors in Brussels on Monday.
The reforms to be voted on later Sunday would reduce Greece's highest pension payouts, merge several pension funds, increase contributions and raise taxes for those on medium and high incomes.
The austerity measures are part of a package demanded by the European Union and International Monetary Fund in exchange for a 86 billion euro ($95 billion) bailout agreed in July, the third for the debt-laden country since 2010.
Central Athens was largely closed to traffic with a significant police presence in the city although numbers were significantly down on February protests when 40,000 people marched in Athens alone.
"People are tired and disappointed by the leftist government in power... the rallies have not had the scale we had expected," said Maria K, a private sector employee in her fifties who claims to be owed 30,000 euros ($34,000) in back pay from her employer.
She also blamed the Orthodox Easter holidays for reducing the numbers at the protests.
The communist-leaning PAME trade union was the best represented group with as many as 7,000 supporters in Athens and 6,000 in Thessaloniki, according to police.
"Social security, public and compulsory for all. The plutocracy must pay," said the union's banners.
A concert protesting the reforms is planned for Sunday evening on Syntagma Square close to the Greek parliament.
Protesters aligned with the GSEE private workers' union chanted: "No to the dissolution of the social security system."
Prime Minister Alexis Tsipras defended the reforms on Friday, telling lawmakers from his left-wing Syriza party -- which holds a slim majority with 153 seats in the 300-seat parliament -- that they would spare the poorest.
Reforming Greece's bloated pension system is crucial to prevent "the system collapsing in a few years", Tsipras added.
Finance Minister Euclid Tsakalotos has called on the eurozone to back the reforms, warning of a "failed state" if the Brussels talks run aground.
"The elements for closing the first review and providing debt relief are, I firmly believe, all there," according to a letter to the euro area's finance chiefs seen by AFP.
"Nobody should believe that another Greek crisis, leading perhaps to another failed state in the region, could be beneficial to anyone."
Greece's budget deficit has ballooned as it struggles to keep up with mammoth debt payments, which the IMF believes is unsustainable.
In its official agenda for Monday's meeting, the Eurogroup said it would review the "progress achieved" by Greece as well as discussing "possible debt relief measures".
Greece is in the grip of the third day of a strikes that have paralysed public transport across the country.
During the stoppages, the fourth general strike since Tsipras came to office in January 2015, the public sector has operated at a snail's pace, while most TV and radio stations have refused to air news bulletins.
Despite the pressure from the strikes, Employment Minister Georgios Katrougalos stood by the pension overhaul, pointing to a funding shortfall of two billion euros.
"This reform should have been done decades ago," he said.
Ahead of the Brussels meeting, differences between the creditors themselves have emerged over extra reforms demanded by the IMF that could amount to another 3.6 billion euros of cuts by Greece.
IMF chief Christine Lagarde has warned that there were "significant gaps" in Greece's reform offers, while European Commission head Jean-Claude Juncker said Athens had "basically achieved" the objective of the measures required by creditors.
But both the EU and the IMF have agreed that debt relief could be considered.