Having assets outside of Russia, exposed to the Western financial system, is a huge risk for wealthy Russians.
The US could also impose sanctions based on powers granted by Congress to target anyone conducting significant business with Russian intelligence and defense sectors.
In February, special counsel Robert Mueller indicted 13 Russians and three Russian companies in what Mueller's office described as a plot to wage "information warfare" against the U.S.
President Donald Trump has been criticized for failing to punish Russian Federation for the interference of the president elections against the ongoing investigation by Special Prosecutor Robert Mueller about whether the head of state's election campaign has had unlawful relations with power in Moscow.
Syria war: Rebels 'begin leaving last Eastern Ghouta town'
It will see Russian military police enter the former rebel bastion of Douma and government institutions return, the monitor said. Douma is the last rebel-controlled town in East Ghouta, a collection of rural, working-class suburbs east of Damascus .
The United States plans to introduce new sanctions against Russian oligarchs.
Sources told the news outlet that the move would come under the Countering America's Adversaries Through Sanctions Act (CAATSA), which Congress passed past year to punish Russian Federation for aggressive military action in Ukraine and Syria as well as Moscow's meddling in the 2016 election.
He said Russian Federation had never possessed or produced novichok, the nerve agent used in the attack, and claimed Moscow's offer of consular support to Ms Skripal had been denied.
The White House and Treasury declined comment on whether they planned to impose sanctions this week. CNN's sources did not reveal the names of the oligarchs.
"The administration is committed to implementing the CAATSA law as we have said many times", a senior USA official told the outlet. In recent months, however, it has stopped at least two Russian oligarchs whey they arrived at U.S. airports to question them.