The United Nations has been accused by some of its staff of racism after it issued a survey that included a question asking how they identify themselves, and offered 'yellow' among the possible responses.

The 'U.N. Survey on Racism' was sent to thousands of staff on Wednesday. An email accompanying the survey said it was being carried out as part of U.N. Secretary-General Antonio Guterres' "campaign to eradicate racism and promote dignity."

But the first question, on how staff identify themselves, itself reflected a historic Western racist view of Asians by listing "yellow" as an option, several U.N. staffers told Reuters. Other categories offered were black, brown, white, mixed/multi-racial and any other.