 Complete the following phrase:  To further its goals, the BCP enlisted the support of the leftist in former Internal Macedonian-Adrianople Revolutionary Organization IMARO, who espoused pro-Balkan Federation views. They changed their name to Macedonian Federative Organization known as the Federalists and in 1918 outlined their policy in a manifesto. Its main points being the restoration of Macedonia to its original geographical boundaries. Their policy led them into open confrontation with the right-wing faction of the Internal Macedonian Revolutionary Organization IMRO. At the Balkan Communist Conference in Vienna in May 1922, the Bulgarian delegate Vasil Kolarov first raised the issue of Macedonian and Thracian autonomy. Knowing the proposal was a threat to their countries borders, the Greek and Yugoslav delegates were unable to endorse it at this stage; however, in order for any chance of success, the communists needed the support of the IMRO. In June 1923, the IMRO collaborated with a nationalist military clique and overthrew the Bulgarian government. The government was condemned by the Communist International, as well as the absent communist resistance to it. When the communists did try to revolt during the 