Russian President Vladimir Putin on Monday gave final approval to legislation allowing him to hold office for two additional six-year terms, opening the possibility for him to stay in power until 2036.

The 68-year-old Russian leader, who has already been in power for more than two decades, signed off on the bill Monday, according to a copy posted on the government’s legal information portal.

Putin proposed the change last year as part of constitutional reforms that Russians overwhelmingly backed in a vote in July. Lawmakers approved the bill last month.

The legislation will reset presidential term limits, allowing Putin to run in elections again after his current and second consecutive term expires in 2024.

Putin was first elected president in 2000 and served two consecutive four-year terms. His ally Dmitry Medvedev took his place in 2008, which critics saw as a way around Russia’s limit of two consecutive terms for presidents.

While in office, Medvedev signed off on legislation extending terms to six years starting with the next president.

Putin then returned to the Kremlin in 2012 and won re-election in 2018.

The term reset was part of constitutional reforms that included populist economic measures and sweeteners for traditionalists such as an effective ban on gay marriage.

Russians voted yes or no to the entire bundle of amendments in a vote last summer that was held over the course of a week, in a move authorities said was aimed at limiting the spread of the coronavirus but critics said left the process open to manipulation.

Golos, an independent election monitor, criticised the format of the vote, saying Russians should have been able to vote for each separate change.

It also said it received hundreds of complaints of violations, including people voting multiple times.

Russians ultimately voted 78 per cent in favour of the changes.

Kremlin opponents have said the constitutional reforms were a pretext to allow Putin to become “president for life”. Putin would be 83 or 84 when he leaves office if he is elected and serves two additional terms to their end in 2036.

The bill also includes new requirements for presidential candidates. They must now be at least 35 years old, have permanently resided in Russia for at least 25 years and have never had foreign citizenship or a permanent residence permit from a state other than Russia.

Also on Monday, Putin signed off on legislation banning insults against World War II veterans, with offenders facing possible sentences of up to three years in jail.