Russian President Vladimir Putin has signed a decree temporarily recognizing identification documents issued in areas of eastern Ukraine held by Russia-backed separatists.
The decision will allow people from separatist-held parts of the Donetsk and Luhansk regions of Ukraine to travel, work, or study in Russia.
Ukrainian President Petro Poroshenko denounced Putin's decree, saying it was evidence of the "Russian occupation" of part of his country and a violation of international law.
According to the decree, Moscow will temporarily recognize identity documents, diplomas, birth and marriage certificates, and vehicle-registration plates issued in the two Ukrainian regions.
The decree said the new regulation will be in place until a "political settlement of the situation" in these regions based on the Minsk peace agreements.
According to the decree, Putin signed it "to protect human rights and freedoms" in accordance with "the widely recognized principles of international humanitarian law."
The signing of the decree came amid tougher talk on Russia by the United States.
U.S. Vice President Mike Pence said on February 18 that the United States would "hold Russia accountable" for its interference in Ukraine.
Poroshenko told reporters that he informed Pence about Putin's decree in their meeting on the sidelines of the Munich Security Conference a few hours after Pence addressed the conference.
The Ukrainian president called it "more evidence of the Russian occupation and Russia's violation of international law." He said it was "symbolic" that the decree was issued during the conference, amid criticism by Western officials of Russia's actions in Ukraine.
During his campaign, Trump voiced admiration for Putin and suggested he might scrap sanctions imposed on Moscow over its actions in Ukraine.
Poroshenko said he received a "very strong message supporting Ukraine" in the meeting with Pence and recent telephone talks with Trump and U.S. Secretary of State Rex Tillerson.
Russia seized Crimea from Kyiv's control in March 2014 and has supported the separatists in a war against government forces that has killed more than 9,750 people in eastern Ukraine since April 2014.