A senior adviser to the European Court of Justice says a European Union business may legitimately prohibit an employee from wearing a Muslim headscarf on the job, provided the ban is based on a general company rule prohibiting visible political or religious symbols in the workplace, and not on prejudice against a particular religion.

The headscarf worn by Muslim women is a contentious issue in some European countries, particularly in France.

This is the first time Europe's highest court is handling a case on banning the headscarf, referred to it by a Belgian court hearing a compensation claim from a woman who was dismissed from her job for wearing a headscarf.

The case concerns a woman, Samira Achbita, who was fired by Belgian security firm G4S Secure Solutions after she insisted on being allowed to go to work while wearing a headscarf for religious reasons.The Belgian court asked the European Court of Justice whether forbidding the headscarf violated an EU law prohibiting discrimination on the basis of religion.

"While an employee cannot 'leave' his sex, skin color, ethnicity, sexual orientation, age or disability 'at the door' upon entering his employer's premises, he may be expected to moderate the exercise of his religion in the workplace," Juliane Kokott, the EU court's advocate general, wrote in her opinion published on Tuesday.

The advocate general's findings are not binding but the EU court typically follows the adviser's recommendation. A ruling from the European Court of Justice is expected later this year. The Belgian court will rule on the matter thereafter.

There are already some headscarf bans in schools and public institutions in France and Belgium. However, Germany's top court last year struck down a ban on teachers wearing headscarves in schools.