Russian Defense Minister Sergei Shoigu told his French counterpart in a telephone call on Sunday that the situation in Ukraine was rapidly deteriorating and trending towards "uncontrolled escalation".
In a phone call with French Defense Minister Sebastien Lecornu published by the Russian side, Shoigu said Moscow had concerns Ukraine could use a "dirty bomb" in the conflict, without providing evidence to support the suggestion that Ukraine might use such a weapon.
"They discussed the situation in Ukraine which is rapidly deteriorating," the defense ministry said in a readout of the call. "It is trending towards further uncontrolled escalation."
A so-called dirty bomb uses conventional explosives laced with radioactive material.
The defense ministry did not provide any further information on its statement.