Mandarins at the Foreign Office invited staff to wear Islamic headscarves for the day, claiming they symbolised 'liberation, respect and security'.
The department was accused of backing the 'institutional oppression of women' by giving away taxpayer-funded headscarves at a walk-in event to mark World Hijab Day.
The event was held as women in ultra-conservative Iran burned their headscarves in protest at being forced to wear them or face arrest and prison.
Many Muslim women across the world have shunned the hijab – which covers the hair and neck but not the face – as an antiquated, oppressive, religious tool.