President Barack Obama delivers remarks on December 11, 2014 in Washington.

The price of the Russian ruble fell sharply against the U.S. dollar Monday after fighting increased in the eastern part of Ukraine and U.S. President Barack Obama raised the prospect of further sanctions against Moscow.

The greenback appreciated to 65.5660 against the Russian currency in morning trade on Monday after ending Friday's session at 64.0100. This was a 2.4 percent jump during the morning session and was due to an "increased sanctions risk" and the lower price of oil according to a note by Timothy Ash, head of emerging market research at Standard Bank. Russian stocks on the Russian MICEX index were lower by 2.5 percent at 9:30 a.m. GMT on Monday.