MOSCOW, March 4 (RAPSI) – As the US considers imposing sanctions against Russia, concerns loom that Russia may be forced to declare its inability to pay off loans issued by US banks, Presidential aide Sergei Glazyev told RIA Novosti.

“Economic sanctions are a double-edged sword, and if the US will freeze our assets, that means our companies’ dollar assets will be frozen too. That means Russian banks and organizations won’t be able to pay off loans to our American partners,” Glazyev said.

According to US Treasury data from the end of 2013, Russian investments in US government bonds total around $139 billion out of a total of $5.8 trillion of US debt held in foreign hands.

Officials in the United States and Europe have told Russia that its actions in Ukraine could lead to economic sanctions and asset freezes.

The Russian ruble hit a record low Monday as stock markets in Moscow fell more than 11 percent after trading began.

Such a crash was widely predicted by experts when Russia’s upper house of Parliament approved the use of military force in Ukraine on Saturday, which was criticized by the US and a number of European countries.  Notably, US Secretary of State John Kerry told NBC’s “Meet the Press” show Sunday that the United States and some of its allies were “prepared to go to the hilt to isolate Russia.”

Speaking before the UN Security Council, Russian Ambassador to the UN Vitaly Churkin said that Russia is authorized to place up to 25,000 military personnel in the autonomous republic of Crimea upon bilateral agreement with Ukraine. According to Churkin, personnel is used for security measures to resist extremists whose actions may put civilians under threat.

On Monday Russian investigators initiated a terrorism case against the leader of ultra-nationalist, far-right Ukrainian movement “Right Sector” Dmitry Yarosh. He is accused of having made a public call to anti-Russian forces to engage in terrorist acts and extremism on Russian territory.