Vladimir Putin's inner circle: Who's who, and how are they connected?

Updated 1143 GMT (1943 HKT) March 28, 2017

Moscow (CNN)He's one of the most powerful men in the world. Born in St Petersburg in 1952, Vladimir Putin worked as a KGB spy in East Germany before going into politics -- working his way up from the mayor's office in St Petersburg to the top job of President.

Estimates of his personal wealth vary wildly -- officially he owns a small apartment, garage and a few cars, but at least one estimate puts his personal wealth at up to $200 billion.
According to Putin's spokesperson, Dmitry Peskov, suggestions of vast wealth are a "perverted commenting of reality."
The Russian President does, however, have many wealthy friends who are alleged to have benefited from their links to him.
These are the people who make up his inner circle.

Igor Sechin

Russia's President Vladimir Putin talks to Rosneft President Igor Sechin in Moscow in 2013.
As the head of one of the world's largest oil companies, Rosneft, Igor Sechin is one of the most powerful men in Russia.
Like Putin, Sechin has come a long way since the early 1990s when the two men worked together in the St Petersburg mayor's office. After he followed Putin to Moscow, Sechin continued to work closely with his old boss -- both as his presidential aide and then as deputy prime minister.
In 2014, after Russia annexed Crimea from Ukraine, and after his stint in Putin's administration, Sechin was put under sanctions by the US treasury which said he had "shown utter loyalty to Vladimir Putin - a key component to his current standing."

Gennady Timchenko

Billionaire Gennady Timchenko, taking part in the St Petersburg International Economic Forum 2014.
With a fortune of about $15.5bn, Gennady Timchenko is ranked 85 on Forbes' billionaires list.
Although he has a luxurious lifestyle now -- and played hockey with Putin -- he has not always been so wealthy. Timchenko comes from humble beginnings -- his wife Elena said the couple used to live in a communal apartment in St Petersburg with "bedbugs and the smell of borscht soup in the kitchen." Their elder daughter, she said, first slept in a suitcase in their room.
Timchenko says he has known Putin for more than 20 years but says "when I am asked questions about our friendship, I always say, please turn to Vladimir Vladimirovich. If I call myself a friend of his, it wouldn't look appropriate."
Timchenko is one of the founders of Gunvor -- a global company that trades in oil and energy markets.
Like other members of Putin's inner circle, Timchenko has been sanctioned, forcing him to ground his private jet in Moscow after Gulfstream refused to service the aircraft.
The US Treasury has claimed that "Timchenko's activities in the energy sector have been directly linked to Putin. Putin has investments in Gunvor and may have access to Gunvor funds." Gunvor has denied this, saying "President Putin has not and never has had any ownership, beneficial or otherwise in Gunvor."
After being slapped with sanctions, Timchenko is reported to have said "you have to answer for everything, even your friendship with the president."
As a sign of Timchenko's closeness to Putin, he was gifted a puppy by Putin from his beloved dog Connie, according to Russian media reports.

Dmitry Medvedev