Kremlin spokesman Dmitry Peskov said U.S. President Joe Biden’s characterization of Russian leader Vladimir Putin as a war criminal was “unacceptable and unforgivable rhetoric”.

U.S. President has for the first time called Vladimir Putin a “war criminal” over the Russian president’s invasion in Ukraine.

“I think he is a war criminal”, - Biden told reporters.

The U.S. administration had avoided using the phrase until now, even when asked directly.