Crimean Tatar leader Mustafa Dzhemilev has been barred from entering Crimea for the next five years.
A spokeswoman for the Mejlis, the Crimean Tatars' assembly, said Dzhemilev was informed he was persona non grata until 2019 as he crossed to mainland Ukraine early on April 22.
The order came three days after he was briefly detained at a checkpoint while entering Crimea.
Dzhemilev has accused Crimea's new pro-Russian government of overseeing what he says is a campaign of repression against Crimean Tatars since the peninsula was annexed by Russia last month.
He says many Crimean Tatars have already lost their jobs after refusing to apply for a Russian passport.
The Mejlis has refused to recognize Crimea's new leadership and the referendum on Crimea's cessation from Ukraine.