Workers who have been absent from work for an extended period of sickness will be entitled to full paid holiday rights.

That is according to a European Court of Justice ruling, which stated that workers in that situation are still entitled to full paid annual leave.

The ruling stated that: “A worker does not lose his right to paid annual leave because of sickness and must be compensated for annual leave not taken.”

The decision by the European Court of Justice reverses a previous ruling made at the Court of Appeal that stated workers on long-term sickness were not eligible to claim holiday.

Mark Mansell, head of employment at city law firm, Allen & Overy, advised companies that the ruling could prove costly for employers who have a “backlog of accrued holiday entitlement” from employees returning to work.

According to research, up to a quarter of workers were expected to call in sick on Monday January 19th as it had been pinpointed by psychologist Dr Cliff Arnall as Blue Monday.