Russian President Vladimir Putin has ordered authorities to temporarily recognise passports and civil registration documents issued in rebel-held areas of eastern Ukraine.
The decision, condemned by Ukrainian President Petro Poroshenko, will reportedly allow people from the conflict-torn area to travel, work and study in Russia.
The order recognises documents like diplomas, birth and marriage certificates, identity documents and vehicle registration plates on a temporary basis from the regions of Donetsk and Luhansk.
Poroshenko said while speaking to reporters in Munich, Germany: "For me, this is another proof of Russian occupation as well as Russian violation of international law."
Oleksander Turchynov, secretary of Ukraine's National Security and Defence Council, said: "The Minsk process provides for the de-occupation of eastern Ukraine and its restitution to the legal force of the state.
"By signing this decree, Putin has legally recognised the quasi-state terrorist groups which cover Russia's occupation of part of Donbas."
Russian Foreign Minister Sergei Lavrov, however, said it was humanitarian decision. He also said that heavy military hardware would be withdrawn from the area.
The fighting in eastern Ukraine has once again escalated tensions between pro-Russian rebels and the Ukrainian army. The Minsk agreement signed in February 2015 has been broken at frequent intervals by fighting that Ukraine and Russia accuse each other of instigating. The latest truce began on 23 December, 2016.
Around 9,700 people have been killed in the conflict that began in 2014 following the Russian annexation of Crimea. Russia-backed separatists later launched an insurgency in the east.