Britain said on Thursday that there was “very, very strong evidence” of war crimes in Ukraine and that Russian President Vladimir Putin was behind them, but it stopped short of calling Putin a war criminal.

US President Joe Biden called Putin a war criminal on Wednesday, comments the Kremlin described as “unforgivable.”

When asked if the United Kingdom was willing to echo those remarks, British Foreign Secretary Liz Truss told BBC radio:

“There’s very, very strong evidence that war crimes have been committed and that Vladimir Putin is behind them.”

“It is ultimately a matter for the International Criminal Court to decide who is or isn’t a war criminal, and for us to bring the evidence.”