The Kremlin on Tuesday called Ukrainian President Volodymyr Zelensky a "peculiar kind of Jew", when asked how he could be linked to an attack in Moscow claimed by Islamic jihadists.

Russian officials continue to allege Kyiv was somehow involved in Friday's attack on a Moscow concert hall that killed at least 139 people, an assertion Zelensky has denounced as absurd.

"Well, there is a peculiar kind of Jew over there," Kremlin spokesman Dmitry Peskov said in response to a question about how Zelensky, who is Jewish, may be linked to the attack.

"A Jew who in many ways shows sympathy and inclination to the nationalist spirit that has permeated the leadership of the Kyiv regime," he continued.

He declined to elaborate, citing an ongoing investigation into the concert hall attack.

Moscow has for years tried to paint the pro-Western Ukrainian government led by Zelensky as neo-Nazi and used this as a pretext for its offensive in Ukraine.

Last June, President Vladimir Putin called Zelensky a "disgrace to the Jewish people", a comment that drew a swift backlash from Jewish groups.

When asked about this comment in a BBC interview, Zelensky called Putin "the second king of antisemitism" after Nazi dictator Adolf Hitler.