Russia has relocated up to 1 million people to the annexed Ukrainian region of Crimea, according to Mustafa Dzhemilev, the long-time leader of the Crimean Tatars and Ukrainian President Petro Poroshenko's envoy for Crimean Tatar affairs.

Dzhemilev told Ukrinform on May 27 that Moscow is bringing "large numbers" of people from various regions of Russia to Crimea, which Russia annexed in 2014.

"But this is held as a military secret because they know perfectly well that it is a crime," Dzhemilev said.

He estimated that the total number of Russians brought into the disputed region was between 850,000 and 1 million.

"Russia is now roughly repeating the same strategy that was used during the first occupation [of Crimea] under [Empress] Catherine [the Great]," he said. "At that time it wasn't possible to deport people since there were no railroads. So they simply created impossible living conditions for people in order to force them to migrate. As a result, Crimean Tatars very quickly became a minority people."

The Russian annexation of Crimea and Russian support for separatists in eastern Ukraine prompted the United States, the European Union, and others to impose targeted sanctions against selected Russian individuals and companies.