Former West Bengal Chief Minister, Jyoti Basu, was admitted to hospital on Sunday after experiencing breathing problems.
Mr. Basu, 96, is considered a Marxist patriarch in India and is one of the founders of the Communist Party of India-Marxist (CPI-M). The CPM has held power in West Bengal for three decades.
He was himself State Chief Minister of West Bengal from 1977 to his resignation in 2000.
The vice president of the private hospital said that his release date would be decided by Tuesday by a group of doctors from the medical board.
Several government officials visited Mr. Basu to wish him a fast recovery.