India on Wednesday allowed banks and post offices to exchange old, big bank notes, which are no longer in circulation, with the Reserve Bank of India (RBI) in a month, provided these notes were collected by December 30, 2016, a finance ministry statement said. India's cooperative banks have also been allowed to exchange old currency notes with the RBI, if they had collected these notes by November 14, the statement said. Prime Minister Narendra Modi announced a shock move on November 8 last year to ditch 500 rupee ($7.74) and 1,000 rupee ($15.48) notes - worth a combined $256 billion - that he said were fuelling corruption, being forged and even paying for attacks by militants who target India.