A video has been posted online showing Russia's new T-14 Armata tank, ahead of the vehicle being officially unveiled in the Victory Day parade on May 9.
Number plates in footage indicate that the footage was shot in the Russian Urals, reports Russia Today.
In the video, purportedly recorded by a Russian motorist, a vehicle bearing the insignia of the Russian Federation stops traffic, and the tank rolls past, with the T-14's branded seven wheel design and 125mm extended length smoothbore gun.
The leak comes as Russian spending on armaments soars, with spending on military research and development set to increase by 20 per cent in 2015, state news agency Tass reported earlier this month.
The Armata system that the tank is based on was designed by the Uralvagonzavod Research and Production Corporation, and developed over five years.
Oleg Siyenko, general director of the company, that a number of tanks and military vehicles built on the Armata system would be showcased at the Red Square parade this year.
Reportedly, 20 units of the tanks have been manufactured and issued to troops for practical training.
Armata tanks have been included in Russia's 2015 defence order, with 2,300 to be ultimately deployed.