Russian President Vladimir Putin has signed a decree fast-tracking Russian citizenship for more Ukrainians, a controversial new move expected to deepen the crisis between the two countries.
The latest move comes during a hugely sensitive transitional period in Ukraine where a comedian with no political experience, Volodymyr Zelensky, won a landslide victory in a presidential election last month.
Some analysts see it as a Kremlin test for the new administration in Kiev.
Putin had already signed a decree on April 24 allowing people living in breakaway regions of eastern Ukraine to receive a Russian passport.
The Russian president said last weekend he was "thinking" about providing citizenship to "all citizens of Ukraine," sparking fury in Kiev.
The new Kremlin decree published Wednesday said several categories of Ukrainian nationals will have the right to receive a Russian passport within three months of applying for one.
Those categories include Ukrainians who already have Russian residence permits and Ukrainian citizens who were born in Crimea but left the peninsula before Russia annexed it in March, 2014.
Around 3 million Ukrainians reside in Russia.
- 'Rights and freedoms' -
The fast-track procedure is implemented to protect "rights and human and civil freedoms", said the decree which Putin signed on Monday.
There were hopes bilateral ties might improve under a Zelensky presidency but that is now looking unlikely, analysts say.
The Kremlin has not congratulated Zelensky and said it was too early to say if it can work with the 41-year-old political novice.
Zelensky is due to take office by early June.
Some in Kiev and the West worry that Moscow's offer of citizenship to Ukrainians would give the Kremlin a justification to freely move troops across the border under the pretext of protecting the interests of Russian nationals.
The West have condemned the Kremlin, accusing Putin of seeking to further destabilise Ukraine, while critics at home say the move would be a major burden for the already-struggling Russian economy.
The EU has called the passport scheme a fresh assault on Ukraine's sovereignty, while Kiev appealed to the UN Security Council to take action.
President-elect Zelensky has called for more sanctions against Russia but also pledged to grant Ukrainian citizenship to Russians who "suffer" under Kremlin rule.
After a pro-Western uprising in Kiev ousted a Kremlin- backed regime in 2014 Moscow annexed Crimea and extended support to Russian-speaking separatists in eastern Ukraine.
- 'Escalation attempt' -
On Wednesday, Ganna Gopko, head of the international affairs committee in Ukrainian parliament, said the latest Kremlin decree showed Putin pressed ahead with his efforts to divide the ex-Soviet country.
"It is a flagrant interference in Ukraine's internal affairs, especially during a transitional period," Gopko told AFP.
"Such Russians actions are an attempt at escalation."
Zelensky has said he doubted many Ukrainians would take Moscow up on its offer because a Russian passport means "the right to be arrested" and "the right not to have free and competitive elections."
Timothy Ash, a strategist at BlueBay Asset Management, suggested that Putin might be testing the new administration in Kiev as well as US President Donald Trump's support for him.
On election night Zelensky appeared to taunt Putin when he told people in fellow post-Soviet countries that "everything is possible."
Ash said Putin "probably did not appreciate Zelensky's comments."
"His nightmare is a truly democratic, open (and) free election, where the people actually get to chose between a range of candidates," he told AFP.
Critics led by outgoing President Petro Poroshenko doubt Zelensky will be able to stand up to Putin.
Nationals of Afghanistan, Iraq, Yemen and Syria who were born in the Soviet Union can also apply for Russian citizenship, the Kremlin decree said.