The opinion, handed down this morning after the broadcasting union Bectu became the first individual union ever to take the government to the European Court, is almost certain to be upheld by the ECJ judges.

It will then be referred back to the British court where the action was started. The government will be made to delete those sections of the Working Time Regulations that require an employee to have 13 weeks of employment with the same employer in order to be entitled to paid leave.

Stephen Cavalier, head of Employment Rights at Thompsons, the leading trade union law firm, said that the government would be wrong to wait for the ECJ ruling.

"The Advocate General has said the right to paid leave is a fundamental human right. The government should now honour its commitment to human rights and the rights of people at work and change the law now, rather than wait to be forced.

"To change the law now would enable millions of workers to take advantage of their new rights this summer, rather than have to wait many more months."