It is hoped that Greece's six-day working week plan will help combat undeclared work that leads to tax evasion, according to Greek public broadcaster ERTNews. Photo: Getty Images

New legislation, which came into effect at the start of July, allows employees to work up to 48 hours in a week as opposed to 40.

It only applies to businesses which operate on a 24-hour basis and is optional for workers, who get paid an extra 40% for the overtime they do.

However, the move by the Greek government is at odds with workplace culture elsewhere in Europe and the US, where four-day working patterns are becoming more common.

Firms adopting these policies typically argue that working fewer hours actually boosts productivity and staff wellbeing.

It is hoped that Greece's six-day working week plan will help combat undeclared work that leads to tax evasion, according to Greek public broadcaster ERTNews.

Tourist businesses and the food industry are not included in the policy.

Greek prime minister Kyriakos Mitsotakis said the "nucleus of this legislation is worker-friendly, it is deeply growth-oriented", the Guardian first reported.

"And it brings Greece in line with the rest of Europe."

The EU’s "working time directive" requires member states to guarantee a 48-hour limit to weekly working hours, including overtime.

Trials of a four-day week in Iceland were deemed an "overwhelming success" and led to many workers moving to shorter hours, according to researchers, which claimed productivity remained the same or improved in the majority of workplaces.