Sanctions have blocked payments to holders of Russian debt, Bloomberg reported.

Read here European Commission unveiled the new package of sanctions

The grace period on the missed bond payments – blocked because of wide-ranging sanctions – ends on Sunday night. There won’t be an official declaration, but if investors don’t have their money by the deadline, there will be an "event of default" on Monday morning, according to the bond documents.

The last time Russia fell into default vis-à-vis its foreign creditors was more than a century ago, when the Bolsheviks under Vladimir Lenin repudiated the nation’s staggering Czarist-era debt load in 1918.