The ban on wearing face-covering garments such as a burqa or niqab in government buildings and on public transport will be evaluated after three years, rather than the customary five, broadcaster NOS said on Wednesday.

The ban, 13 years in the making, is due to come into effect on August 1, but there remain many unanswered questions about how it will work in practice.

In particular, questions have been asked about the apparent refusal of public transport companies to take action against burqa and niqab wearers, and similar statements from hospital chiefs.

The law states that people who wear any face covering garment in public buildings, hospitals, schools and on trams and trains, face a fine of €150.

No-one knows how many women in the Netherlands wear the fundamentalist Islamic garment, but estimates range from 100 to 400.