Vladimir Putin has held power for 20 years but he is still well behind the record terms of Cuba's late Fidel Castro and North Korea's founder Kim Il Sung. He is also far from achieving the lengthy stints of many living leaders, with Equatorial Guinea's Teodoro Obiang Nguema the longest-serving president at 40 years.

Britain's Queen Elizabeth II is the longest-reigning monarch at 67 years. Putin first came to power as prime minister of Russia in 1999, being elected president the following year.

In 2008, after two presidential terms, he handed the role to Dmitry Medvedev and stepped back to become prime minister again.

He returned to the Kremlin in 2012, triumphing at the polls in 2018 for a fourth term as president.

To mark his 20 years in office, here are other world leaders who have managed to stay at the top for more than two decades.