Coastal ferries and passenger ships remained docked at ports across Greece on Friday after seamen walked off the job for the fourth straight day.
The union for seamen began their strike on Tuesday and decided to extend it until at least dawn on Sunday, or even longer if their demands are not met.
Residents on hundreds of small Greek islands without airports have been cut off from the mainland because of the strike, with medication and food supplies left in trucks and containers at ports.
The strike seemed to have little impact on ferry traffic between Greece and Italy.
The Panhellenic Seamen’s Federation is demanding that its members’ jobs be safeguarded with 10 months employment per year and the creation of an independent unemployment fund for seamen.
The seamen are protesting the government’s austerity programme and demanding a two per cent pay rise, 1.5 per cent more than shipyards are offering.
The cash-strapped Mediterranean country is implementing a wave of economic reforms as part of a bid to slash public spending in exchange for a 110-billion-euro (150-billion-dollar) rescue package from the European Union, European Central Bank and International Monetary Fund.
Unions are strongly opposed to the austerity measures, which include the scrapping of overtime pay and bonuses, and have for months been organizing strikes and demonstrations.