The Kremlin has denied reports that a longtime key aide to President Vladimir Putin is stepping down.
The resignation of Vladislav Surkov was reported by Aleksei Chesnakov, an adviser to Surkov and director of Moscow's Center for Political Studies.
In a Twitter post on January 25 on Twitter, Chesnakov said Surkov was resigning due to what he called a "change of course on Ukraine."
However, Kremlin spokesman Dmitry Peskov said there is no decree yet on Surkov's resignation. He also told Russian media that there had been no change in Kremlin policy on Ukraine.
"As for the alleged change in the policy on the situation in Ukraine, this has nothing to do with reality and reflects only a personal viewpoint of the person who speaks about that," Peskov told the TASS news agency.
Surkov has played a leading Russian role in negotiations on ending the conflict in eastern Ukraine, where more than 13,000 people have died in fighting between Russia-backed separatists and Ukrainian government forces since April 2014. Hostilities erupted there shortly after Russia annexed Ukraine's Crimean Peninsula.
Widely known as the Kremlin's "gray cardinal," Surkov helped craft the Kremlin's domination of domestic politics and Russia's expansionist policies in Ukraine and elsewhere in the former Soviet space.
Surkov also helped build what is known as "sovereign democracy" and, as Putin's top political aide, concentrate power in the president's hands during his first two presidential terms between 2000 and 2008.
He was pushed from the Kremlin in 2011, after street protests against the system he helped create, and spent a year in government as a deputy prime minister before quitting in May 2013 after a dispute with investigators looking into suspected fraud.
In September 2013, Putin appointed Surkov as an aide, just four months after he quit the government.
He also serves as an adviser to Putin on aid to the Moscow-backed breakaway Georgian regions of Abkhazia and South Ossetia, which Russia recognized as independent after a short war in 2008 with Georgia.