In December 1905, the Ukrainian Social-Democratic Labour Party (USLDP) decided to join the Russian Social Democratic Labour Party, provided it was recognised as "the sole representative of the Ukrainian proletariat", within the RSDLP. The Fourth (Unity) Congress of the RSDLP rejected the proposal which the USDLP spokesman had made for the immediate discussion of the terms of a merger, and referred the matter to the Central Committee for decision. At the USDLP party congress in June 1907 the party adopted its resolution that was similar to ultimatum urging RSDLP to recognize Ukrainian autonomy, Ukrainian Social-Democracy must have its representative in the Central Committee of RSDLP, and accept USDLP as the RSDLP's national organization of Ukrainian proletariat. No agreement was reached on a merger. Arguably, the reason that there was no merger was the fact that the USLDP, the UPSR, and the URLDP all favoured an independent Ukrainian state.