Announced after market hours on Friday, the measure underscores the RBI’s shrinking flexibility. Efforts to defend the rupee have led to a sharp drop in foreign-exchange reserves, potentially constraining the central bank’s ability to intervene forcefully as the currency hit record lows following the Iran war. India’s forex reserves have fallen by more than $30 billion in the first three weeks of March, according to the latest data, partly reflecting such interventions, analysts say.