Why Did India’s 1991 Economic Reforms Begin During a Balance-of-Payments Crisis?

I’m trying to understand the connection between India’s 1991 balance-of-payments crisis and the economic reforms that followed. Was the crisis mainly the immediate trigger for policy changes, or had the government already been considering a similar shift before the foreign-exchange shortage became acute?

For anyone studying this period, which events best explain the timing and shape of the reforms? I’m interested in the economic pressures as well as the political decisions behind them.