A court in Moscow has ordered Yulia Navalnaya, the widow of late Russian opposition politician Alexei Navalny, arrested in absentia for two months.

The court accused Navalnaya, who lives outside Russia, of participating in an “extremist” group.

The decision means she would face certain arrest if she sets foot in the country.

Navalnaya, 47, has stepped into the spotlight after her husband’s death in an Arctic penal colony in February, and said she would continue the fight for what Navalny called the “beautiful Russia of the future”.

Writing on X on Tuesday, Navalnaya told her supporters to focus not on the court order against her, but on the battle against Russian President Vladimir Putin.

“When you write about this, please don’t forget to write the main thing: Vladimir Putin is a murderer and a war criminal,” she wrote.

“His place is in prison, and not somewhere in The Hague, in a cozy cell with a TV, but in Russia — in the same [penal] colony and the same 2-by-3-metre cell in which he killed Alexei.”

The Kremlin has denied ordering Navalny killed.

Since her husband’s death, Navalnaya has met several senior foreign leaders, including US President Joe Biden in San Francisco.

The US-based non-profit group Human Rights Foundation named Navalnaya its chairwoman last week, and she said she would use the new role to step up the struggle waged by her husband against Putin.

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“We will take on board everything that can be useful to fight Putin, to fight for the beautiful Russia of the future,” Navalnaya said on X.