On December 8, 1991, at Viskuli near Brest (Belarus), the President of the Russian SFSR and the heads of Byelorussian SSR and Ukrainian SSR signed the "Agreement on the Establishment of the Commonwealth of Independent States" (known in media as Belavezha Accords). The document, consisting of a preamble and fourteen articles, stated that the Soviet Union ceased to exist as a subject of international law and geopolitical reality. However, based on the historical community of peoples, relations between them, given the bilateral treaties, the desire for a democratic rule of law, the intention to develop their relations based on mutual recognition and respect for state sovereignty, the parties agreed to the formation of the Commonwealth of Independent States. On December 12, the agreement was ratified by the Supreme Soviet of the Russian SFSR by an overwhelming majority: 188 votes for, 6 against, 7 abstentions. On the same day, the Supreme Soviet of the Russian SFSR denounced the Treaty on the Creation of the USSR and recalled all Russian deputies from the Supreme Soviet of the Soviet Union. The legality of this act is the subject of discussions because, according to the 1978 Constitution (Basic Law) of the Russian SFSR, the Russian Supreme Soviet had no right to do so. However, by this time the Soviet government had been rendered more or less impotent, and was in no position to object. Although the December 12 vote is sometimes reckoned as the moment that the RSFSR seceded from the collapsing Soviet Union, this is not the case. It appears that the RSFSR took the line that it was not possible to secede from an entity that no longer existed.
Is there an answer to this question (If it cannot be answered, say "unanswerable"): What body ratified the Belavezha Accords on December 12?
the Supreme Soviet of the Russian SFSR