The Kremlin is considering options on bringing the private military group Wagner under its direct control after the presumed death of its leader, Yevgeny V. Prigozhin, according to U.S. and Western officials.

Among those possibilities, officials say, are absorbing Wagner into the Defense Ministry or its military intelligence arm. The Kremlin could also install a Russian general or other government ally as its new chief, according to people briefed on the preliminary intelligence.

Officials stressed that the future of Wagner, which Russia depended on as a parallel fighting force in Ukraine until it fell out of the Kremlin’s favor after a short-lived mutiny in June, was not at all clear. Still, U.S. officials said the Kremlin believes the organization’s military prowess, experienced operators and ties to African governments are too valuable to give up or allow to wither away.

A plane believed to be carrying Mr. Prigozhin crashed on Wednesday, Russian, U.S. and European officials have said. U.S. officials said the plane appeared to have been downed on the orders of President Vladimir V. Putin of Russia, as revenge for Mr. Prigozhin’s aborted mutiny. He had sent a column of mercenaries toward Moscow in an attempt to oust the leadership of the Defense Ministry. U.S. officials believe an explosion aboard the plane, possibly a bomb, brought down the plane.

The officials, who spoke on the condition of anonymity, said the Kremlin appeared not to have made any final decisions on what to do with Wagner and, as a result, the intelligence picture was evolving.

No matter what option the Kremlin chooses, U.S. and Western officials said, there are myriad challenges for the Russian government.

If the Kremlin tries to absorb Wagner into the G.R.U. or the broader Ministry of Defense, a major question would be whether veteran Wagner mercenaries would trust, or even accept, any sort of government takeover. A mass exodus could follow.

But there are also other complications, including what to do with the company’s moneymaking endeavors in Africa, and if they would be successful as a state-controlled operation.

American officials believe Mr. Putin wants to assert direct control and does not intend to allow the company to choose its own replacement for Mr. Prigozhin. In early July, following Mr. Prigozhin’s initial rebellion, the Kremlin moved to dissolve the Internet Research Agency, the troll farm and influence operation Mr. Prigozhin had founded and used to attack Hillary Clinton during the 2016 election. But the Kremlin did not shut down Wagner, allowing some of its most experienced fighters to take refuge in Belarus even as it enticed others to sign contracts with the Defense Ministry.

Pentagon officials say that under Mr. Prigozhin, the Wagner forces were Russia’s most effective combat forces on the battlefield in Ukraine, notably in the fight to seize the city of Bakhmut in the east. But Wagner forces have since withdrawn from Ukraine, and most have relocated to Belarus.

“For all intents and purposes, their combat effectiveness has been diminished. And they are no longer a significant factor when it comes to the conflict inside Ukraine,” Brig. Gen. Patrick Ryder, the Pentagon spokesman, told reporters on Thursday.

Having the G.R.U. absorb Wagner or a military general take it over would be a logical step for the Kremlin, U.S. officials said.

The military intelligence service worked closely with Wagner forces in Africa, sometimes devising operations that the mercenary group supported, to some degree. The company’s work there often blends soft power with blunt force. Wagner’s operations in Ukraine were much more in line with conventional military operations, throwing waves of poorly trained convicts against Ukraine’s military. Absorbing Wagner would expand the G.R.U.’s hard military power, but the two organizations also operate in similar ways, hiding their true intentions and operating in the shadows. While the intelligence service’s operations often fall short of their tactical goals, G.R.U. has exemplified the kind of aggressive hybrid intelligence service Mr. Putin wanted, blending propaganda, influence campaigns, hacking attacks and assassinations to carry out Russian intelligence and foreign policy goals.

General Ryder said the United States would keep a close watch on Wagner’s work in Africa, even with the demise of Mr. Prigozhin. “I don’t think anybody’s going to discount the potential for danger when it comes to that group or the remnants of that group,” he said.

On Friday, The Wall Street Journal reported that a G.R.U. general was poised to take over Wagner’s African operations.

The G.R.U. — in particular, one of its clandestine arms, Unit 29155 — planned and carried out the attempted assassination in Salisbury, England, of Sergei V. Skripal, the former Russian intelligence officer who had been sent to Britain in a spy swap, according to British and American officials.

The unit has also been accused of crafting a destabilization campaign in Moldova, poisoning an arms dealer in Bulgaria and orchestrating an attempted coup in Montenegro. Some American officials also believe Unit 29155 was involved in a plan to pay bounties to Taliban members who killed American service members in Afghanistan.