Vladimir Putin has appointed Alexei Dyumin, his former bodyguard, as secretary of the advisory State Council, fuelling speculation about his presidential potential.
The president has brought Mr Dyumin, 51, closer to the centre of power since his re-election in March, having made him an aide overseeing the defence industry this month.
The details of his new role are unknown.
"Russia's elite is abuzz with the appointment of Dyumin," Sergei Markov, a former Kremlin adviser and Putin supporter, said on Telegram.
"This is seen as confirmation that Dyumin is the future president of Russia, Putin's choice," Mr Markov said, adding that this was something that had long been rumoured.
There is no public debate or reliable information about who
might eventually succeed Putin, who is 71 and is expected to
rule for years, but his appointments are scrutinised for signs of whether he is lining up a potential candidate to one day take over from him.
Being publicly identified as a potential successor carries certain risks attached to being seen as a challenger.
Asked about Dyumin's appointment, the Kremlin said it was part of a rotation - he is taking over the role from Igor Levitin, 72 - and said he would look at how the State Council would function.