Convoy of the UN special envoy to Yemen Martin Griffiths arrives at the Sanaa International Airport, Yemen, on Feb. 18, 2019. The United Nations Special Envoy to Yemen Martin Griffiths left the rebel-held capital Sanaa on Monday after a one-day visit in which he cemented a peace deal reached in Stockholm December last year. Based on Griffiths' plan, the warring parties agreed on a first phase to withdraw from the ports of the Red Sea city and facilitate access by the UN humanitarian aid workers to reach grain aid in the city's mills, according to a UN statement. (Xinhua/Mohammed Mohammed)