The strike is causing disruption at the height of the tourist season

Trains, airlines and passenger ferries have had limited services, causing disruption at the height of Greece's tourist season.

Bank workers, hospital employees and civil servants are also taking part.

Parliament is debating a draft law which would allow employers to impose more flexible working hours.

An ongoing government drive to reform the labour market and increase productivity has sparked opposition from the unions, leading to strikes in several sectors over recent months.

The unions were expected to hold a mass demonstration later on Tuesday in front of the Greek parliament.