President Vladimir V. Putin of Russia replaced his minister of defense on Sunday as he shook up his national security team for the first time since his invasion of Ukraine.
Mr. Putin kept the minister, Sergei K. Shoigu, in his inner circle, tapping him to run the country’s security council.
Andrei R. Belousov, an economist who served as first deputy prime minister in the last government and previously was the economic development minister, was nominated to become the new defense chief.
It is unclear how much authority over the war effort Mr. Shoigu will retain.
The Kremlin also said that Nikolai P. Patrushev, a former K.G.B. colleague of Mr. Putin who has headed the Russian security council for 16 years, would be moved to another position to be announced in the coming days.
Russian commentators quickly expressed surprise over the appointment of an economist to oversee Russia’s sprawling military. The Kremlin’s spokesman, Dmitri S. Peskov, told reporters that Mr. Putin made the decision because of the sharp rise in the defense budget over the last two years.
“It is very important to fit the economy of the security bloc into the country’s economy, to fit it in so that it corresponds to the dynamics of the current moment,” Mr. Peskov said.
It was a rare shake-up for Mr. Putin, who values loyalty and stuck by Mr. Shoigu despite Russia’s military failures early in the war and the embarrassing mutiny last summer by the mercenary chief Yevgeny V. Prigozhin.
The possible shift in Mr. Shoigu’s stature had been signaled last month, when the Russian authorities arrested one of his top deputies on corruption charges. His replacement with Mr. Belousov — long seen as one of Mr. Putin’s most trusted economic advisers — also highlights the Kremlin’s success in keeping the Russian economy afloat in the face of Western sanctions.
The change comes less than a week after Mr. Putin was inaugurated to his fifth term as Russia’s president. The Russian leader’s entire cabinet was dispersed as part of the government transition. Many but not all of his ministers were renominated to their posts.
Gen. Valery V. Gerasimov, the chief of the Russian general staff and the highest-ranking Russian military officer, will remain in his post, the Kremlin said.
