The currency is down by 0.6% at 64.3917 per dollar as of 7:37 a.m. ET.
The ruble's tumble follows Friday's dip in oil prices. Brent crude oil, the international benchmark, is down 1.5% at $49.24 a barrel.
Moreover, Bloomberg's Ksenia Galouchko reported that Sberbank CIB analyst Iskander Lutsko said that "the ruble is too expensive compared to oil and the budget. Everyone understands that it hurts the economy."
As for the rest of the world, here's the scoreboard as of 7:43 a.m. ET.
- The Korean won closed down 0.4% at 1,103.54 per dollar after the Bank of Korea held rates at 1.25%, as expected.
- The euro is little changed at 1.1270 against the dollar after Germany posted a 19.4 billion euro trade surplus in July, below expectations of 22.0 billion euro.
- The US dollar index is essentially unchanged at 95.00 ahead over several data points. Wholesale inventories will cross the wires at 10 a.m. ET and the Baker Hughes rig count will be announced at 1 p.m. ET.
- The Japanese yen is up by 0.3% at 102.77 per dollar