Two former U.K. prime ministers, Gordon Brown and Sir John Major, are calling for the creation of a new international tribunal modeled on the Nuremberg trials to investigate Russian President Vladimir Putin and his accomplices for their actions in the invasion of Ukraine.

“From Britain—which rightly prides itself in democracy and the rule of law—the message must go out. At Nuremberg we held the Nazi war criminals to account. Now, eight decades on, we must ensure there will be a day of reckoning for Putin.” Brown said in a statement.