After the end of the Cold War, there were two tank manufacturing plants in Russia, Omsktransmash who worked on the T-80 and Uralvagonzavod who worked on the T-72 and the now T-90. The T-90 was a stop gap whilst waiting for a new fourth generation principal Main Battle Tank for the Russian Ground Forces.
The Russian Black Eagle Main Battle Tank
Omsktransmash did develop a working fourth generation prototype based on the T-80 called Black Eagle, (aka Object 640) which was publicly displayed in 1999 and it was believed that this would become the new principal Main Battle Tank for the Russian Ground Forces, however the company went bust in 2002 and the Black Eagle project ceased.
Uralvagonzavod are the developers of a second fourth generation principal Main Battle Tank design called the T-95. Government funding for the T-95 development ended in 2010 and swapped to the The T-14 Armata. The T-14 has been accepted in to Russian Army with 2300 budgeted for and expected to enter service between 2015 and 2020 as the Russian Ground Forces principal Main Battle Tank.