The move sparked outrage in Russia, where Putin’s press secretary Dmitriy Peskov rejected the findings. “We do not recognize this court, we do not recognize the jurisdiction of this court. This is how we treat this,” he said in a Telegram post.

Moscow has consistently denied allegations of war crimes, describing them as a “fantasy” aimed at discrediting Russia. Russia’s embassy to the United States said last month that the country had taken in children forced to flee the fighting.

Although Moscow formally withdrew its signature from the founding statute of the ICC in 2016, the ICC move will obligate the court’s 123 member states to arrest Putin and transfer him to the court’s headquarters in the The Hague, Netherlands, if he does cross their borders.

However, most governments also abide by an international legal principle that heads of state have legal immunity from other courts.

Inside Russia, the U.K.’s Defense Ministry said in an intelligence briefing Saturday that the Kremlin was ramping up military conscription to meet war needs and was likely to change the age rules and restrictions around who was eligible to serve.

Officials in Russia’s Parliament, the Duma, introduced a bill on Monday to change the age bracket of conscription to men between the ages of 21 and 30, it said in the daily note that was posted to Twitter. Currently the age range is 18 to 27, it said, adding that the new law would take force in January.

“The authorities are highly likely changing the age bracket to bolster troop numbers by ensuring that students are eventually forced to serve,” the briefing said. 

Although Russia continues to officially bar conscripts from operations in Ukraine, “at least hundreds have probably served through administrative mixups or being coerced to sign contracts,” it said. 

This will free up a greater proportion of professional soldiers to fight, even if conscripts are not deployed into conflict in Ukraine, the briefing said.