Ukrainian President Volodymyr Zelensky on Sunday made a surprise video appearance at the music industry's star-studded Grammy Awards celebration in Las Vegas and appealed to viewers to support his country "in any way you can."

"What is more opposite to music? The silence of ruined cities and killed people," said Zelensky in the video that introduced John Legend's performance of "Free" and featured Ukrainian musicians and a reading by Ukrainian poet Lyuba Yakimchuck.

"Fill the silence with your music. Fill it today, to tell our story. Support us in any way you can. Any, but not silence," Zelensky, wearing his now trademark olive green T-shirt, said in English, his voice hoarse.

War broke out in Ukraine over a month ago after Russian military forces invaded, displacing millions of civilians and reducing cities to rubble. Russia calls its actions in Ukraine a "special operation".

Actor-turned-wartime-leader Zelensky, 44, has used nightly videos to great effect at home, often appearing unshaven and wearing a T-shirt, and has also beamed his image directly to parliaments around the world.

He has pleaded with allies in speeches at the U.S. Congress, Japanese National Diet, British and Australian parliaments and Israeli Knesset, and on Sunday chose an event dedicated to the universal language of music to spur support for his country.

"Our musicians wear body armor instead of tuxedos, they sing to the wounded, in hospitals, even to those who can't hear them but the music will break through," he said.