Greek ships remained in port and train services were halted as workers walked off the job on Tuesday to protest against planned labour reforms that include the extension of working hours in the private sector.
The walkout, the second this month by Greece's main public and private sector unions GSEE and ADEDY, was timed to coincide with a vote this week on the conservative government's suggested reforms.
Thousands of striking workers, including teachers, hospital doctors and journalists, rallied in central Athens and marched to parliament as lawmakers debated the bill. Protest rallies were planned in big cities across the country.
The draft law allows private sector employers to seek up to 13 hours of work a day from their staff compared with the current eight hours. It also gives them more flexibility on short-term hirings and amends rules on the distribution of annual leave.
The government says the bill creates a more effective and flexible labour market, allowing employees to work four days a week. It also protects workers from being fired if they refuse to work overtime and extends their benefits, according to the labour minister.
But unions say it hurts workers' rights and strips them of their negotiating power in a country where there is undeclared work and average wages are still low compared with other EU countries, despite pay increases and lower unemployment after a debilitating debt crisis from 2009 to 2018.
Greeks' purchasing power is among the lowest in the European Union, Eurostat data shows. The country also has the highest share in the EU of employees working more than 45 hours a week, according to the bloc's statistics agency.
Opposition parties demanded that the bill be withdrawn.
"The 13-hour shift cannot become a reality. It's paid slavery," Effie Achstsioglou, a lawmaker with the small New Left party, told parliament.

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