It has long been suspected that the Russian premiere has a secret fortune valued as high as $70 billion. With the Obama administration ready to add a new round of sanctions as early as Monday, it appears that the U.S. is trying to make it clear to Putin that it knows where his money is hidden. Putin is rumored to secretly control significant portions of Russia's largest energy companies, including as much as 75 percent of Gunvor, whose co-owner was targeted last month in sanctions. Though the US has not specifically placed sanctions against Putin yet, the sanction targets are moving closer into his inner financial circle. “It’s like standing in a circle and all of a sudden everyone in the circle is getting a bomb thrown on them, and you get the message that it’s getting close,” said Senator Robert Menendez.