President Volodymyr Zelenskyy of Ukraine. Photo: EPA

Ukrainian president Volodymyr Zelenskyy has asked those in Russia who oppose Vladimir Putin’s regime to "do something concrete to change the situation", in a rare address to Russian citizens.

Russia has passed draconian laws aimed at stifling any dissent with the full-scale invasion of Ukraine, which is still officially called in Moscow a ‘special military operation’.

In an interview with Italian channel Sky TG24, Mr Zelenskyy admitted it is very difficult to send any messages to Russia, but urged Russians who oppose Mr Putin to "keep moving forward".

"There is no other way out. Ukraine must defeat the enemy," he stressed.

"Europe must support Ukraine for the sake of common values, and people in Russia must do something concrete to change the situation."

Opinion polls suggest most Russians support the war against Ukraine and Vladimir Putin, although it is difficult to verify since people might be wary of voicing what they really think.

A number of Mr Putin's critics have been jailed, including opposition activists Alexei Navalny, Illya Yashyn and Vladimir Kara-Murza, and some have left Russia for fear of persecution.