Gulzarilal Nanda became India's first acting Prime Minister in 1964 after Jawaharlal Nehru's death, serving for 13 days. He again acted as PM in 1966 after Lal Bahadur Shastri's death. V.V. Giri later became acting PM in 1969, while Morarji Desai and Charan Singh became full Prime Ministers in 1977 and 1979 respectively.