The latest comments by Medvedev, who is a key aide to President Vladimir Putin, follow Putin's nuclear warning last week and his Sunday remarks casting Moscow's confrontation with the West as an existential battle for the survival of Russia and the Russian people.
The Russian official reiterated his threat of nuclear war over Ukraine if Western countries continue to arm Ukraine despite repeated warnings from Moscow.
"Of course, the pumping in of weapons can continue .... and prevent any possibility of reviving negotiations," Medvedev said in remarks published in the daily Izvestia.
"Our enemies are doing just that, not wanting to understand that their goals will certainly lead to a total fiasco. Loss for everyone. A collapse. Apocalypse. Where you forget for centuries about your former life, until the rubble ceases to emit radiation."
MNA/PR