The India central bank is selling dollars in the onshore spot market on Friday and had intervened in the non-deliverable forward market prior to the onshore open amid volatility fuelled by the tensions in the Middle East, four traders said.

The rupee was at 83.4950 to the U.S. dollar, having opened at an all-time low of 83.5750.

"The RBI (Reserve Bank of India) has consistently been on the offer since the open," a trader at a private sector bank said.

"And they smacked NDF before 9.00 today."

The onshore over-the-counter markets open at 9.00 a.m. IST. (Reporting by Nimesh Vora; Editing by Savio D'Souza)