In the Russian system, alliances of business oligarchs, generals, governors, intelligence officers and oil company chiefs compete for power and money. Mostly out of public view, they disseminate kompromat, or comprising information about each other, and arrange for rivals to be arrested or driven into exile.

Mr. Putin, rather than the courts, arbitrates these disputes, preventing escalation. Were he actually to retire, abdicating this role, “there would be civil war,” said Konstantin Gaaze, a sociologist at the Moscow School for Social and Economic Sciences, who specializes in Russian patronage networks.

Fights have already come to light. In 2017, for example, a former economy minister and member of a liberal wing of Russian politics, Aleksei V. Ulyukayev, became embroiled in a feud with the powerful director of the state oil company, Igor I. Sechin.

Ultimately, he was convicted of accepting a bribe of $2 million from the oil company that came in a holiday gift bag that also held homemade sausages. Mr. Ulyukayev, who is serving an eight-year sentence in a penal colony, says the charge was trumped up.

The changes announced by Mr. Putin seem designed to maintain his perch as the arbiter of these disputes. They would drain power from the presidency and split it between the Parliament and a newly empowered body called the State Council, weakening the presidency before any potential successor occupies the post.

Another change might safeguard Mr. Putin against foreign legal action, such as lawsuits related to the downing of a civilian airliner in Ukraine by a Russian missile in 2014, if he steps aside from the presidency. Mr. Putin suggested a measure to prohibit enforcement of treaty obligations if they violate Russia’s Constitution.