The rupee is down nearly 19 percent so far this year despite efforts by policymakers to prop it up.
Anticipation of a Western operation against Syria had driven the WTI contract to its highest level since May 2011 this week, while Brent also soared to its highest price in six months.
Indian Oil, BPCL and HPCL are the three companies that are the biggest buyers of dollars in the currency markets, requiring about USD 8.5 billion every month to import an average 7.5 million tonnes of crude oil.
The Reserve Bank on Thursday opened a special window to help meet the foreign-exchange requirements of the state-owned OMCs.