who was the prime minister then?
Morarji Desai
Neelam Sanjiva Reddy
Morarji Desai 
who has been the only lok sabha speaker to have become the president of india Neelam Sanjiva Reddy when did he become the president? 21 July 1977 whom did he defeat in the election? The presidential election of 1977 was necessitated by the death in office of the incumbent Fakhruddin Ali Ahmed. Reddy was elected unopposed
wiki:14116000
Neelam Sanjiva Reddy [SEP] Presidential election of 1977
The presidential election of 1977 was necessitated by the death in office of the incumbent Fakhruddin Ali Ahmed. Although Prime Minister Morarji Desai wanted to nominate danseuse Rukmini Devi Arundale for the post, she turned down the offer. Reddy was elected unopposed, the only President to be elected thus, after being unanimously supported by all political parties including the opposition Congress party. At 64, he became the youngest ever person to be elected President of India. He was also the only serious presidential candidate to have contested twice – in 1969 against V V Giri and in 1977. 37 candidates had filed their nominations for the presidency of whom 36 were rejected by the returning officer.