In a surprise move, the Central government has demonetised Rs 500 and Rs 1,000 currency notes. The move is aimed at fighting black money. Ever since the policy came into effect, people have queued up outside ATMs and banks to withdraw notes or exchange old currencies. The opposition has slammed the government with Trinamool's Mamata Banerjee calling for a rollback. Demonetisation has led to a logjam in Parliament. Demonetisation is a radical monetary step in which a currency unit’s status
as a legal tender is declared invalid. This is usually done whenever there is a change of national currency, replacing the old unit with a new one. In India, it was first implemented in 1946 when the Reserve Bank of India demonetised the then circulated Rs 1,000 and Rs 10,000 notes.