After a gap of 15 years Mahathir bin Mohamad is once again Malaysia's Prime Minister, and his re-election means he's also a record holder.
At the age of 92 years 141 days, he is now the Oldest current Prime Minister having been born on 20 December 1925.
First day on the job... once again. pic.twitter.com/Oxe3E8OEuU— Dr Mahathir Mohamad (@chedetofficial) May 11, 2018
Mahathir also served as Prime Minister for 23 years from 1981-2003 and came out of retirement 15 years after stepping down as his country's leader to stand for re-election.
Having initially been a member of the Barisan National coalition, which had been in power since 1957, the 92-year-old joined the Pakatan Harapan (Alliance of Hope) coalition ahead of this week's election.
His election victory means he's older than the two previous serving politicians who Guinness World Records has recognised as holding the title.
Previous record holders
King Fahd bin Abdul Aziz
Saudi Arabian ruler, King Fahd, assumed the office of Prime Minister on 13 June 1982 on the death of his brother, King Khalid.
Born in 1921, he was the Oldest current Prime Minister by the time he passed away on 1 August 2005, aged 84.
King Abdullah Ibn Abdul Aziz
After King Fahd's passing, he was replaced as Saudi Arabia's Prime Minister by King Abdullah, three year's his predecessor's junior.
King Abdullah was born in 1924 and remained in the post until his death at the age of 90 in January 2015.
But other politicians have stayed in power long enough to set records.
Other prime ministerial records
The Oldest appointed Prime Minister, where a politician has been made their country's leader for the first time, is Morarji Ranchhodji Desai.
Born in 1896, he became Prime Minister of India in 1977 at the age of 81.
The Oldest UK Prime Minister in office is William Gladstone (UK, 1809-98), who was 84 years 64 days old when he left office on 3 March 1894.