By Laurence Peter and Pavel Aksenov, BBC News, 6 May 2015
Russia will stage its biggest ever military parade on 9 May, to mark the 70th anniversary of victory over Nazi Germany in World War Two.
A rehearsal in central Moscow has revealed some new hi-tech Russian armour for the first time, lifting a veil of military secrecy. The most talked-about innovation is the Armata T-14 battle tank, described as a new-generation fighting machine to replace Soviet-era tanks.
The tank is highly automated - the Russian military says it could be the basis for a fully robotic tank in future.
It has a remote-control gun turret with a 125mm smooth-bore cannon that can fire guided missiles as well as shells.
The crew of three is housed in a reinforced capsule at the front, away from the firing systems.
The Armata's chassis is adaptable - it can also serve as the platform for a heavy infantry fighting vehicle, an engineering vehicle, a multiple rocket launcher and some other variants.
Russia plans to bring in about 2,300 Armatas, starting in 2020, to replace Soviet-era tanks. They are built by UralVagonZavod.
Jane's Defence Weekly says the T-14 and Russia's other new armoured systems are "principally clean-slate designs" that "represent the biggest change in Russia's armoured fighting vehicle families since the 1960s and 1970s"