Mr Singh, 77, who was suffering from blood cancer and chronic renal failure, died in the afternoon in New Delhi’s Apollo hospital, a hospital spokesman said.
Prime Minister Manmohan Singh, no relation to the deceased, said India had lost a great patriot whose empathy for the country’s poorer classes would always be remembered.
Mr Singh served as finance and defence minister in the late prime minister Rajiv Gandhi’s cabinet but later parted ways with Mr Gandhi.
He is best known for his policy of reserving government jobs for India’s disadvantaged castes, which sparked off widespread protests from the country’s upper classes.—Reuters