1956 Suez Campaign mail: December 1956 stampless cover on United Nations (UN) stationery from UN Suez Canal Clearance Group at PORT SAID to UN Office of the Controller NEW YORK, carried "via UN [diplomatic] Pouch" per instructional marking on front & tied by illustrated bilingual Arabic-English circular handstamp of the Suez Canal Clearance Group, enabling the mail for postage-free official mail service; front-stamped 21 Dec. 1956 arrival using red-ink UN dater-handstamp; back tied by small double-ringed red negative seal (in English) of the Clearance Group. The Suez campaign lasted from 29 October to 7 November: in November the Egyptian government confirmed the existence of mines in the approaches to the Suez Canal, and clearance operations began in late December. Kibble reports seeing only 2 such covers, of which this is one. Slit open at top.