The Greek–Yugoslav confederation or federation, or Balkan Union, was a political concept during World War II, sponsored by the United Kingdom and involving the Yugoslav government-in-exile and the Greek government-in-exile. The two governments signed an agreement pushing the proposal ahead, but it never got beyond the planning stage because of opposition from within the Yugoslav and the Greek governments, real world events, and the opposition of the Soviet Union. The proposal envisioned the creation of a confederation of Greece and Yugoslavia. Background Greece and Yugoslavia were occupied by Nazi Germany and formed governments-in-exile in London. Establishment of the union was the first step of the British "Eden plan": its final aim was to create a central-eastern union that was friendly to the west. The next step was to include Albania, Bulgaria and Romania into a Balkan Union. The last step was to be folding of the Balkan Union with a Central European federation formed by Hungary, Czechoslovakia and Poland. The first step was restricted to only Yugoslavia and Greece because they were the only countries that supported the Allies. Agreement The two governments-in-exile negotiated the conditions of the agreement until the end of 1941. The agreement was signed by Slobodan Jovanović and Emmanouil Tsouderos on the ceremony held in British Foreign Office, presided by the British Foreign Minister Anthony Eden. The agreement explicitly stated that both governments looked forward to accede other countries of the Balkans to the Union. quoted in Although caution was advised with revealing the hope that Bulgaria and Romania would join the union, on 4 February 1942, Eden stated in the House of Commons that the treaty signed between Yugoslavia and Greece was going to be a basis for the establishment of the Balkan confederation. Encouraged by the British Foreign Office, together with the Polish-Czechoslovak confederation, they were to form a pro-Western organisation of states between Germany and the Soviet Union. Both governments-in-exile agreed to form a political, economic and military union, with the motto "The Balkans for the Balkan People". Their governments would not be unified but there would be much coordination between their respective parliaments and executives. Their respective monarchies were to be unified with the marriage of King Peter of Yugoslavia to Princess Alexandra of Greece. The union was to be finalised after the war. The marriage of Peter and Alexandra proved to be a problematic move and reduced support for the union