Shushkevich discovered the disappearance of the original document while working on his memoirs. Officials with Belarus' government and Russia-dominated alliance of ex-Soviet nations confirmed Wednesday they only have copies.
The document's disappearance reflects the chaos that surrounded the Soviet demise.
On Dec. 8, 1991, Shushkevich hosted Russia's President Boris Yeltsin and Ukraine's President Leonid Kravchuk for secret talks at a government hunting lodge near Viskuli in the Belovezha Forest. The trio signed a deal declaring that "the U.S.S.R. has seized to exist as a subject of international law and geopolitical reality," defeating Soviet President Mikhail Gorbachev's attempts to hold the country together and forcing him to resign on Christmas Day.