New Delhi, March 14 -- India's dollar stockpile had its biggest weekly gain in over three years, bolstered by the Reserve Bank of India's currency swap operations last month.

Foreign exchange reserves grew by $15.3 billion to nearly $654 billion in the week to March 7, data released on Thursday showed. That is the highest weekly gain since Aug. 27, 2021, according to Bloomberg-compiled data.

This comes after the central bank injected $10 billion through a foreign-exchange swap auction on Feb. 28, stepping up efforts to ease a cash crunch in the financial system. The swap entails the central bank purchasing dollars from banks against the rupees they hold, while contracting to sell the greenback at a future date.

"The swap essentially ad...