“17.04.63 Secretary of State Dean Rusk told President [John F.] Kennedy that American efforts to reduce allies’ vessel traffic to Cuba have been successful: the governments of Liberia, Turkey, Honduras and Panama had officially forbidden their vessels to do trade with Cuba; Western Germany had issued a decree prohibiting freighters in their registry to participate in trade between the Soviet bloc and Cuba; the Greek government had ordered its vessels that had not been chartered to the Soviet bloc to stop carrying cargo to Cuba; the Lebanese government had promised to review its laws to accommodate the U.S. policy objectives. The British, however, were an obstacle. Whitehall insisted that there was no legal basis to prevent navigation to Cuba. Mr. Rusk made several proposals based on this information: 1) the United States should make another proposal to the United Kingdom, both through its Ambassador in Washington and in London, seeking British cooperation and pointing out the need for a major American action unless a prompt reduction of British shipments to Cuba was achieved. 2) Similar proposals should be addressed to Norway, Italy and Spain. 3) The United States should prepare for release at a given moment, an extension of the provisions in the National Security Action 220 to vessels owned or controlled by people involved in trade with Cuba giving a 45-day grace period to allow for the redirection of their vessels in the course of their voyage. 4) To request oil companies, owned or controlled by the United States that they voluntarily refrain from supply freighters known to be involved in trade with Cuba, and seek British cooperation in the implementation of a similar policy by British oil companies.” [Pro Embargo]

“John F. Kennedy (D). Timeline,” Cuba versus Blockade: Cuban People’s website, 2007