On September 14, Ambassador Winthrop Aldrich in London delivered the United States proposal regarding Trieste (see Document 110) to Lord Salisbury, Acting Foreign Secretary, who expressed a desire to delay an official reply until the end of the month when it was expected that Foreign Secretary Eden would return to the Foreign Office. (Telegram 1092 from London, September 14; 750G.00/9–1453) On September 15, the Department of State instructed Aldrich to press the British Government for an answer since it believed that Prime Minister Pella might not wait until the end of September to bring the Trieste matter to a head and to confront the United States and the United Kingdom with a public request for turning over Zone A to Italy. (Telegram 1338 to London, September 15; 750G.00/9–1553) On September 16, Aldrich reported that the British Government had given its general agreement to the United States proposal, but that it believed it advisable to delay action in order to allow passions to die down. The Foreign Office had also expressed concern over the degree of pressure that could be exerted on Tito. Before the two governments reached a firm decision on the United States proposal, the Foreign Office considered it essential to have the advice of the British and United States Embassies in Rome and Belgrade. (Telegram 1135 from London, September 16; 750G.00/9–1653)
There followed two weeks of intensive discussions involving the British and United States Governments and their respective representatives in Rome and Belgrade. In general, United States officials continued to believe it possible to guide Italy and Yugoslavia into annexing each of the zones. British officials, while basically in agreement with the plan, were more skeptical of the chances for success. To coordinate the details of the implementation of the plan, the British Government at the end of September decided to send Nicholas J.A. Cheetham, Head of the Foreign Office Western and Southern Department, to Washington.
These developments, including the recommendations from the United States Embassies in Belgrade and Rome and the official response of the British Government to the United States proposal, as communicated in a memorandum of September 23, were summarized [Page 280] in memoranda of September 21, 25, and 28, from Walter K. Scott of the Executive Secretariat to Secretary Dulles. (750G.00/9–2153; 750G.00/9–2553; and 750G.00/9–2853, respectively)