KUALA LUMPUR: Pakatan Harapan chairman Tun Dr Mahathir Mohamad has officially been sworn in as Malaysia's seventh Prime Minister.

Dr Mahathir took his oath of office as Prime Minister before Yang di-Pertuan Agong Sultan Muhammad V at the Istana Negara at 9.57pm Thursday (May 10).

The 92-year-old was accompanied by his wife Tun Dr Siti Hasmah, PKR president Datuk Seri Dr Wan Azizah Wan Ismail, DAP secretary-general Lim Guan Eng, Parti Amanah Negara president Mohamad Sabu, Parti Pribumi Bersatu Malaysia president Tan Sri Muhyiddin Yassin and PKR vice-president Nurul Izzah Anwar.

This means that Dr Mahathir will be the world's oldest prime minister and the first Malaysian to be premier twice.

Dr Mahathir was previously prime minister from 1981 to 2003, the longest-serving in Malaysian history.

At a press conference earlier, Dr Mahathir said he would appoint Dr Wan Azizah as deputy prime minister once he is sworn in.

Dr Mahathir received the mandate to form the government through Pakatan, which managed to wrest 113 out of 222 federal seats in GE14.

At least another ten MP's have also indicated their support for the coalition, making it a total of 123 MP's who support Dr Mahathir.

These are Parti Warisan Sabah, which has eight parliamentary seats, as well as independent Batu MP P. Prabakaran and Upko acting president Madius Tangau, the Tuaran MP.