Greece's two main unions on Thursday said they would hold a two-day general strike next week against new austerity cuts by the government to address an unravelling debt crisis that has shaken the eurozone. The leading GSEE union that represents private sector employees said the strike would be held on October 19 and 20, revising earlier plans for a one-day action. "Our fight will continue and intensify for as long as these futile and disastrous policies continue," GSEE said in a statement. The mobilisation will be supported by Adedy, the country's second-largest union representing civil servants, a spokesman told AFP. It is timed to coincide with a vote in parliament on a new batch of austerity measures adopted by the government to persuade its international creditors to release loan funds next month to avert a national bankruptcy. A barrage of strikes has hit the country this week, shutting down museums and archaeological sites and snarling public transport in Athens. A general transport strike will be held in the capital on Friday and customs inspectors are starting a 10-day walkout, raising the prospect of fuel shortages. Civil servants will see further wage cuts on top of sacrifices last year and most Greeks will suffer tax break cuts as the state struggles to economise to meet fiscal targets slipping away due to a growing recession. In particular, staff at several listed state companies face salary cuts of 65 percent on average compared to 2009 levels, Finance Minister Evangelos Venizelos told parliament. The reforms are mandated by the European Union, the International Monetary Fund and the European Central Bank, which last year earmarked a 110-billion-euro ($151-billion) loan for Greece. Matthias Mors, the EU head representative on an audit mission closely monitoring the economic overhaul, on Thursday said additional measures worth five billion euros were agreed with the Greek government to bridge deficit gaps in 2011 and 2012. Speaking to Greek daily Kathimerini, he added that the government ought in the next six months to determine extra steps to meet fiscal targets for 2013 and 2014. The three creditors, or 'troika', have asked the government to limit the application of collective wage agreements to private companies in order to increase labour flexibility and competitiveness. EU-IMF experts argue this is the best way to tackle mounting unemployment in the country which unions say could hit 20 percent next year. Changes to collective labour agreements are a condition for the continued disbursement of EU-IMF loan funds, Venizelos said. The international trade union confederation said the labour reform -- which gives groups of employees the power to sign company agreements instead of unions -- threatens core labour rights fought and won over a century. Over a thousand public workers demonstrated in Athens on Thursday to protest against the cuts which they say are driving salaries to sub-poverty levels. Other unionists blocked the interior ministry, forcing Interior Minister Haris Kastanidis to postpone a press conference on tackling a ten-day protest by garbage collectors that has accumulated thousands of tonnes of refuse in Athens and Thessaloniki.