Prior to their usual 10:30 a.m. Moscow time (06:30 GMT) opening, both exchanges said would remain closed and were awaiting further instructions, although an RTS spokesman said it would allow trading in repo contracts and bond repurchases.
No official information has so far been available on when the two bourses will resume trading.
"It cannot be excluded that trading will be resumed after the State Duma adopts a package of anti-crisis measures," said Alexei Serov, acting chief analyst at the Financial Bridge asset management company.
The Dow Jones index plummeted Thursday below 9,000 points for the first time since 2003, and the S&P index dropped 7.6% to 909.92 points despite the move by central banks around the globe to cut interest rates.
European stock exchange indexes fell 1.2%-2.5% Thursday, and the Asian stock markets have been sinking Friday on the back of the U.S. falls.
U.S President George W. Bush is expected to address the nation later Friday. According to the White House press secretary, Dana Perino, Bush plans to assure Americans that his administration will do its best to overcome the crisis.
The British FTSE 100 and Germany's DAX index plunged by more than 10% Friday, and the French CAC index lost 9.77%.