Earlier this week, Reuters reported that the RBI has been intervening in non-deliverable forwards and the onshore over-the-counter (OTC) market to keep the rupee from breaching its record low of 83.29 against the U.S. dollar.

Its likely intervention in exchange-traded derivatives is reflected in the more-than-$1 billion jump in open interest on September USD/INR futures over the last three sessions on the National Stock Exchange, which represents a major chunk of the open interest on rupee futures.

"This big a jump in open interest in a span of few days is highly unusual," said Abhilash Koikkara, head - forex and rates at Nuvama Professional clients group.

"It is likely that the RBI is stepping in to curb volatility on the back of higher crude and U.S. yields."

The RBI did not immediately respond to a Reuters email seeking comment.

A futures trader at a private sector bank said that on a few occasions this week, there has been "a sudden" 2 to 3 paisa dip in USD/INR currency futures and "a slight deviation" from the spot OTC price.

"This, alongside the OI (open interest), suggests RBI selling," the trader said.

A part of the surge in open interest can be explained by speculators chasing the USD/INR higher and "a bit of hedging" after 83 was breached, said Dilip Parmar, an analyst with HDFC Securities.

(Reporting by Nimesh Vora; Editing by Savio D'Souza)

By Nimesh Vora