The third phase is characterized by the clash between the Balkan Communist leaders and Joseph Stalin, the latter of whom opposed the idea during the post-World War II period.
They confirmed their adherence to the ideals of French Revolution in the line of Saint-Simon's federalism and in relation to the socialist ideas of Karl Marx or Mikhail Bakunin.
This proposal was controversial within the Greek government and Venizelists because it went against the nationalist ideals of Venizelism and Venizelos', the fact that it would damage Greco-Italian relations due to the fact that a semi-united Balkan federation would damage Italian influence and it would also hurt other Great Powers (The United Kingdom, France and the United States of America) as it would also limit their influence in the Balkan peninsula, another setback on the proposal was that Yugoslavia and Bulgaria barely took any interest in it.
In 1915, Dimitrov wrote that Macedonia, "... which was split into three parts ...", would be, "... reunited into a single state enjoying equal rights within the framework of the Balkan Democratic Federation.
Later he made his way to Russia, where he joined the Bolshevik Party after the October Revolution in 1917, and subsequently Dimitrov, Kolarov, and Rakovsky became members of the Comintern.
After the Russian October Revolution, a Balkan Communist Federation was formed in 1920–1921, and was influenced by Vladimir Lenin's views on nationality (see Proletarian internationalism).
It advocated a "Balkan Federative Republic" that would have included Bulgaria, Yugoslavia, Greece, and Turkey; some projects also involved Romania, but most of them only envisaged its fragmentation.
In Sofia, Bulgaria in May–June 1922 the question of the "autonomy of Macedonia, Dobruja and Thrace" was raised by Vasil Kolarov and was backed by Dimitrov, the Bulgarian delegate who presided over the meeting.
The BKP was compelled by Stalin to endorse the formation of Macedonian, Thracian, and Dobrujan nations in order to include those new separate states in the Balkan Communist Federation.
The KKE delegate Nikolaos Sargologos signed the motion without central authorisation; instead of returning to Athens, he emigrated to the United States.
[6] By 1935, it simply called for "equal rights to all" due to the "change of the national composition of the Greek part of Macedonia" and hence because "the Leninist–Stalinist principle of self-determination demands the substitution of the old slogan".
The KPJ had its own problems and dissentions; fears of Serbianisation of the party and of the Vardar Banovina, whose inhabitants felt closer (though not necessarily identified) to Bulgaria than the Kingdom of Yugoslavia.
In the early 1920s, two entities came in contact with the Comintern: the left-wing opposition led by Bishop Fan Noli, and the Committee of Kosovo.
The introduction of Fascist Italy's interests in the equation completely disrupted any connection between Albanian nationalist movements and the Comintern.
For a short period during the Cominform, the Yugoslav and Bulgarian Communist leaders Josip Broz Tito and Georgi Dimitrov worked on a project to merge their two countries into a Balkan Federative Republic.
[13] The policies resulting from the agreement were reversed after the Tito–Stalin split in June 1948, when Bulgaria, being subordinated to Soviet interests, was forced to take a stance against Yugoslavia.
[19] In his interview with Nick Holdstock during the 2012 Subversive Film Festival in Zagreb, Pakistani-British political activist and writer Tariq Ali argued for the creation of the Balkan Federation as a part of wider formation of European regional federations capable of balancing the influence of the major European powers such as Germany or France.