What is the ruling of Islamic law regarding the work of an expatriate official if it requires his wife to remove her hijab at official events?

The Islamic head covering (hijab) is an obligatory duty upon the Muslim woman, based on the Qur'an, Sunnah, and the consensus of Muslims. It is forbidden for her to uncover what must be covered in front of non-mahram men. Violating this is considered a major sin.

If a husband is pleased with his wife's display of her adornments and her appearing unveiled and intermingling with non-mahram men, then he is a dayyuth (pimp/cuckold) whom Allah will not look at on the Day of Resurrection. A dayyuth is a man who approves of indecency and wickedness in his family and his female relatives and has no protective jealousy over them.

The claim of social advancement does not justify this act. True advancement lies in adhering to Allah's commands and prohibitions, not in imitating others and abandoning one's identity.