He also served as the assistant director-general for external relations and public information at UNESCO Headquarters in Paris between 2010 and 2018.

[2][3] In 1991, Falt had his appointment with UN as a press attache to the Office of Permanent Representative of France to the United Nations.

In 1992, he was appointed as a spokesman for the United Nations Transitional Authority in Cambodia, which oversaw and sponsored the 1993 Cambodian general election.

[2] Between 2002 and 2007, he simultaneously served as the director of both the Communications for the United Nations Environment Programme and the UN Information Centre in Nairobi, Kenya.

He later directed the Outreach Division of the United Nations Department of Public Information in New York,[3] before moving to United Nations Educational, Scientific and Cultural Organization (UNESCO) headquarters in Paris in 2010,[4] as the assistant director-general for external relations and public information.