Greek taxi owners launched a second week of strike action on Monday in a protest against government deregulation that has caused major disruption at the height of the busy summer tourist season.
Thymios Lyberopoulos, president of the Attica taxi owners' union, said the strike would go on indefinitely, while plans were underway for a demonstration at the parliament in central Athens on Tuesday.
The protest began last Monday in response to a government decision to deregulate the taxi sector as part of efforts to liberalise the nation's struggling economy, a key demand of Greece's foreign creditors.
Taxi owners argue that full liberalisation will sink the value of their operating licenses, which until now were worth hundreds of thousands of euros (dollars).
The protest at the height of the holiday season has angered tour operators and Tourism Minister Pavlos Geroulanos who said the action was damaging the country's reputation abroad.
In the first days of the strike unionists blocked highways feeding into Athens, the capital's airport and its port.
Threatened with arrest, they have since been gathering at road toll stations where they have been allowing cars to pass without paying.
The European Union and International Monetary Fund have demanded sweeping deregulation in various Greek labour sectors in exchange for multi-billion-dollar loans needed to save Athens from defaulting on its debt.
The tourism industry, vital to the country's economy, desperately needs holidaymakers to visit through the summer high-season.