Vladimir Putin has signed a law that will allow him to run for the presidency twice more in his lifetime, potentially keeping him in office until 2036.

The Russian president signed the legislation on Monday, ending a year-long process to “reset” his presidential terms by rewriting the constitution through a referendum-like process that his critics have called a crude power grab.

Putin has been Russia’s most powerful politician since he assumed the presidency in 2000, after the resignation of his predecessor, Boris Yeltsin.

If he remains in power until 2036, his tenure will surpass even that of Joseph Stalin, who ruled the Soviet Union for 29 years, making Putin the longest-serving Moscow leader since the Russian empire.

Officially, the new law limits Russian citizens to two presidential terms in their lifetime, outlawing the kind of shuffling between the presidency and the role of prime minister that Putin employed earlier in his career.

But the law specifically does not count terms served until it entered into force, meaning that Putin’s past four terms (including the current term) do not count and he can still serve two more. Russians say that he has “zeroed out” his terms.

Analysts have said the law may not indicate that Putin wants to remain president, but simply wants to avoid being a lame duck and provoking a power struggle during his last term in office.