Kakar, the 52-year-old first-time Senator, is an ethnic Pushtun from Balochistan and a member of the Balochistan Awami Party (BAP) -- a party considered close to the powerful establishment of the country, NDTV reported.
He was administered the oath of office by President Arif Alvi in a ceremony held at the Aiwan-i-Sadr (the President House) in Islamabad. He became the 8th interim prime minister of Pakistan.
Ahead of taking the oath, Kakar resigned from the upper house of Parliament.
Kakar's name was agreed upon during the final day of consultations between Prime Minister Shehbaz Sharif and the Leader of the Opposition in the dissolved National Assembly, Raja Riaz Ahmad on Saturday.
Senate Chairman Sadiq Sanjarani on Monday accepted Kakar's resignation from the Senate ahead of the latter's swearing-in as the caretaker prime minister.
A day earlier, Kakar announced his resignation from the Senate as well as the Balochistan Awami Party (BAP), which he founded in 2018.
According to Geo News, Kakar stepped down from his post because he wanted to be an impartial interim premier.
Since it was his responsibility to hold free and fair general elections in cooperation with the Election Commission of Pakistan, he decided to resign.
A notification issued by the Senate Secretariat on Monday notified Mr Kakar's resignation.
SD/PR