[1] A plan to control materials coming into the country was put forward in early 1937, effectively subjecting the Spanish Republic to severe international isolation and a de facto economic embargo.The German position was that such a declaration was not needed, but discussions could be held on preventing the spread of the war to the rest of Europe if the Soviet Union was present.Such a declaration had already been accepted by the United Kingdom, Belgium, the Netherlands, Czechoslovakia and the Soviet Union, which renounced all traffic in war material, direct or indirect.An ultimatum was put to Yvon Delbos by the British to halt French exports to Spain, or Britain would not be obliged to act under the Treaty of Locarno if Germany invaded.[12] There was popular support in both countries for the plan, but in the United Kingdom, the socialist Labour Party was strongly for it,[nb 2] the left in France wanted direct aid to the Republicans.[19] Like Labour, between October 1936 and June 1937 and under pressure from the LSI and the International Federation of Trade Unions, Citrine, Bevin and the TUC repudiated non-intervention.[18] A report, Commission of Inquiry into Alleged Breaches of the Non-Intervention Agreement in Spain, was drawn up in London, sponsored by the Comintern and headed by respectable figures.Léon Blum, the French prime minister, feared that openly supporting for the Republic would lead to civil war and a fascist takeover in France and ultimately to no change in Spain.[22] Five days later, the Glenn L. Martin Company enquired whether the government would allow the sale of eight bombers to the Spanish Republican Air Force; the response was negative.On 23 August 1936, it agreed to the Non-Intervention Agreement,[24] which was followed by a decree from Stalin banning exports of war material to Spain, thereby bringing the Soviets into line with the Western powers.[23] Soviet foreign policy considered Collective security against German fascism a priority,[25] and the Comintern had agreed a similar approach in 1934.[5] The Committee first met in London on 9 September 1936 and was attended by representatives of solely European countries and did not include Switzerland, whose policy of neutrality prohibited even intergovernmental action.Germany was represented by Ribbentrop (with Otto Christian Archibald von Bismarck as deputy) but left the running to Grandi[34] although they found working with him difficult.[14] Stanley Baldwin, the British prime minister, and Blum both attempted to halt global exports to Spain and believed it in Europe's best interests.[36] It would have been better to call this the Intervention Committee, for the whole activity of its members consisted in explaining or concealing the participation of their countries in SpainThe second meeting took place on 14 September 1936.[38] It established a subcommittee to be attended by representatives of Belgium, Britain, Czechoslovakia, France, Germany, Italy, the Soviet Union and Sweden to deal with the day-to-day running of non-intervention.[44] On 12 November 1936, significant changes were put in place to the functioning of the committee with the ratification of plans to post observers to Spanish frontiers and ports to prevent breaches of the agreement.U.S. President Franklin Roosevelt, who was also approached, ruled out U.S. interference with the words '[there should be] no expectation that the United States would ever again send troops or warships or floods of munitions and money to Europe'.[nb 4] An armistice would be called, a commission sent to Spain and, after a plebiscite, a government featuring those uninvolved in the war (such as Salvador de Madariaga) would be established.[52] That charge was denied by Lord Cranborne and Édouard Viénot, the British and French representatives respectively, who appealed to the League to endorse the mediation plan.[52] On 6 January 1937, the first opportunity after the winter break, both houses of the U.S. Congress passed a resolution banning the export of arms to Spain[54][nb 5] Those opposed the bill, including American socialists, communists and many liberals, suggested that the export of arms to Germany and Italy should be halted also under the Neutrality Act of 1935 since foreign intervention constituted a state of war in Spain.[61] Observers were posted to Spanish ports and borders, and both Ribbentrop and Grandi were told to agree to the plan, significant shipments already having taken place.It iterated calls for the withdrawal of volunteers from Spain, condemned the bombing of open towns and showed approval of humanitarian work.[71] Britain and France thus continued to labour over non-intervention; although they judged it effective, some 42 ships were estimated to have escaped inspection between April and the end of July.Ciano complained to his government that Italian forces in Italy were ready but not being used; the Soviet Union was not prepared to discuss belligerent rights;[83] Delbos was considering proposing mediation by Roosevelt and the Pope and simultaneously preparing French war plans; and Britain's new prime minister, Neville Chamberlain, saw securing a friendship with the Italian Benito Mussolini as a top priority.[84] Eden confided he wished Franco to win and so Italian and Germany involvement would be scaled back; Chamberlain considered Spain a troublesome complication to be forgotten.[90] On 6 November, the Committee met once again with a plan to recognise the Nationalists as belligerents once significant progress had been made was finally accepted, which was caused partly by Eden's patience.