The head of the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) Martin Griffiths will resign from his post at the end of June due to health reasons, a spokesman for UN Secretary General António Guterres said on Monday. During his tenure which began in July 2021, Griffiths, 72, “advocated tirelessly for life-saving aid to reach those most in need and for the resources needed to do so,” deputy spokesman Farhan Haq said in a statement. “A skilled diplomat and mediator, he has played a key role in leading the humanitarian response of the United Nations and partners and ne…