Greek workers on Wednesday hold their first major anti-austerity strike since a coalition government took power in June, grounding flights, disrupting local transport and shutting public service offices.
Called by the country's two biggest unions that represent half the work force, the walkout is expected to bring out thousands of Greeks to the streets to protest at a new round of belt-tightening demanded by EU and IMF lenders.
"We call on everyone to take part in the strike and resist the austerity measures that hurt Greek people and the economy," said unionist Despoina Spanou of the ADEDY labour group.
"This strike is only the beginning in our fight."
The traditional summer break has allowed the conservative-led government of Prime Minister Antonis Samaras to enjoy relative calm on the streets since coming to power.
But ADEDY and its private sector counterpart GSEE were predicting a big turnout on Wednesday to end the seasonal lull.
About 3,000 police - twice the number usually deployed - will stand guard in the centre of Athens as authorities brace for the rioting that has marked past rallies. Athens last witnessed serious violence in February, when protesters set shops and banks ablaze as parliament approved an austerity bill.
Ships will stay docked, shops will pull down shutters and museums and monuments will be closed to visitors throughout the day on Wednesday. Air traffic controllers will walk off the job for three hours and hospitals will operate on emergency staff.
Much of the union anger is directed at spending cuts worth nearly 12 billion euros ($15.55 billion) over the next two years that Greece has promised the European Union and International Monetary Fund in an effort to unlock its next tranche of aid.
The bulk of those cuts are expected from slashing wages, pensions and welfare benefits, heaping a new wave of misery on Greeks who say repeated rounds of austerity have pushed them to the brink and failed to transform the country for the better.
A survey by the MRB polling agency last week showed that more than 90 percent of Greeks believe the planned cuts are unfair and burden the poor, with the vast majority expecting more austerity in coming years.
But with Greece facing certain bankruptcy and a potential euro zone exit without further aid, Samaras's government has little choice but to push through the unpopular measures, which have also exposed fissures in his fragile coalition.
With Greece in its fifth year of recession and no light at the end of the austerity tunnel, analysts warn that Greek patience is wearing thin and a strong public backlash could tear apart the weak conservative-led coalition.
"What people want to tell Samaras is that they are hurt and Samaras could use this to demand concessions from the troika," said MRB polling director Dimitris Mavros.
"The people are willing to give the government time, but on certain conditions like cracking down on tax evasion and securing a bailout extension. If the government succeeds in that, its life will also be extended."
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