President Vladimir Putin approved legal amendments to make it simpler for Russian speakers in ex-Soviet countries - such as Ukraine - to gain Russian citizenship.
The changes, which were reported by the Reuters, come during a tense period in eastern Ukraine with pro-Russian separatists occupying government buildings and demanding a referendum on whether or not to come under Moscow's rule.
The U.S. says it is sure Moscow is backing the separatists, but Russia denies this. Putin had previously denied backing separatists in the now annexed peninsula of Crimea but last week during a marathon televised question-and-answer session he admitted his forces had supported the uprising.
Reuters contributed to this report.