Habibullah Khan was the first Chairman of the Senate of Pakistan from 6 August 1973 until 5 August 1975, and was consecutively elected chairman for the second term of the Senate from 6 August 1975 until 4 July 1977. He remained acting President of Pakistan from 1977 until 1978, when martial law was imposed on the country by General Muhammad Zia-ul-Haq.
Habibullah Khan was the first Chairman of the Senate of Pakistan from August 6, 1973, to August 5, 1975, and was consecutively elected chairman for the second term of the Senate from August 6, 1975, until July 4, 1977. He remained acting President of Pakistan from 1977 until 1978 when General Muhammad Zia-ul-Haq imposed martial law on the country.