After the resignation of Zimbabwe's President Robert Mugabe, Queen of the United Kingdom, Elizabeth II, became the world's oldest head of state, the Daily Mail reported.

Mugabe, 93, ruled the African country for 37 years. He said on Tuesday he was leaving the presidency. Thus, the 91-year-old British Queen became the oldest of all heads of state in the world.

This is another record by Her Majesty. In September 2015, Elizabeth II passed the Queen Victoria's record of the length of reign on the throne among British monarchs. And after Thailand's Pymilon Yaduliadet died on October 13, 2016, she became the longest-running monarch among the existing kingdoms of the world. On February 6, 2017, the British Queen celebrated the 65th anniversary of her reign on the throne, a sapphire jubilee, with no precedent in the British monarchy.