Russia's Interior Ministry says that some 527,000 people in parts of eastern Ukraine where Moscow-backed separatist formations are waging a war against Kyiv have been granted Russian citizenship over the past two days.
The ministry's press service made the announcement on May 2 to the state news agency TASS.
Earlier, Russia had issued 650,000 new passports in the region after President Vladimir Putin in 2019 issued an order for a simplified and expedited citizenship process for residents of those areas.
Moscow's policy of handing out citizenship in Ukraine has come under intense international criticism as a bid to further destabilize the area, where more than 13,000 people have been killed since the fighting started in April 2014.
Ukraine has condemned the Russian naturalization of Ukrainian citizens as part of a hybrid-warfare campaign being waged by Moscow and a violation of Ukraine's sovereignty.
Russia has provided military, economic, and political support to the separatists in parts of Ukraine's Luhansk and Donetsk regions. Despite overwhelming evidence to the contrary, Moscow maintains it is not involved in Ukraine's domestic affairs.
The developments come at a time of heightened tensions between Russia and Ukraine in recent weeks, when Russia launched a major military buildup along its border with Ukraine and in the Black Sea Ukrainian region of Crimea, which Moscow annexed in 2014.
On April 8, Putin's deputy chief of staff, Dmitry Kozak, said Russia could "be forced to come to the defense" of Russian citizens in Ukraine, a statement that was repeated the following day by Kremlin spokesman Dmitry Peskov.
In November 2020, Peskov said, "Russia has always protected and will continue to protect the interests of Russians, regardless of where they live."
Viktor Vodolatsky, deputy chairman of the Russian State Duma's Committee on CIS Affairs and Eurasian Integration, told TASS on April 24 that Russia could issue up to 1 million new passports to Ukrainians by the end of the year.
On March 20, a Russian presidential decree came into force banning non-Russian citizens from owning land in most of Crimea.
"The European Union does not recognize the illegal annexation of the Crimean Peninsula by Russia, which is a clear violation of international law," said an EU statement at the time.
"Therefore the European Union does not recognize this decree and considers its entry into force as yet another attempt to forcibly integrate the illegally annexed peninsula into Russia."