LONDON — The political risks are rising for Vladimir Putin as the Ukrainian military begins its much-awaited assault to dislodge Russia from territory it illegally seized last year, with the Russian president acknowledging Kyiv's "offensive potential."

There is nervousness among the Russian elite over the firepower of Ukraine's Western weaponry, insiders say, and it is driving fears that the land bridge Moscow carved across the southeast of Ukraine to Crimea could be severed — dealing significant military and morale setbacks to the Kremlin.

In addition, infighting among battlefield leaders, drone attacks on Moscow and a spate of unprecedented incursions by paramilitary groups into western Russian regions bordering Ukraine are raising questions over whether Putin can control the situation, according to several members of the Russian elite, who spoke on the condition of anonymity for fear of reprisal.

"This is a serious challenge for the authorities," said one well-connected member of Russian diplomatic circles.

Signs of the growing tension emerged this month when an influential member of the Russian parliament, Konstantin Zatulin, who is close to the top brass in the Russian intelligence agency, the Federal Security Service, declared at a conference on the future of Ukraine that Russia had so far failed in all of its war aims and that some of them had become "senseless."

"What were the aims announced at the beginning of the special military operation?" Zatulin asked, using the Kremlin's term for the war. "You all remember —denazification, demilitarization, neutrality for Ukraine and the defense of the residents of Donetsk and Luhansk. On which of these points have we reached results today? Not one."

Zatulin's spokesperson did not respond to requests for further comment.

"The mood is very gloomy among the elite," said Tatyana Stanovaya, the founder of R-Politik, a political analysis firm. "They don't understand what Putin's plans are and doubt whether he is adequately dealing with the situation. This has been going on for a long time, but the worry is building up."

The well-connected member of Russian diplomatic circles who remains in contact with government officials said the mood turned gloomier last week after Western proposals emerged for long-term security agreements for Ukraine. That would provide Kyiv with guaranteed arms supplies over a multiyear period as an alternative to immediate NATO membership.

"This determines the main worry of the Russian leadership," this person said. "If contemporary weapons will be supplied and the Ukrainian army will be modernized, then — even without formal membership — Ukraine in this form can represent an existential threat for Russia."

"It seems to me this is further stimulus for Russia to continue the military operation," he added.

Putin had appeared to count on diminishing Western resolve to support Ukraine, especially with a presidential election in 2024 in the United States, where a minority of Republicans have argued against continuing high levels of assistance to Ukraine. In Moscow, that assumption is eroding, insiders say.

"Modest signals" have emerged that Russia could be willing to make some compromises, the well-connected member of Russian diplomatic circles said. Margarita Simonyan, the usually hawkish head of RT, the Russian state propaganda TV channel, this month called for the conflict to be frozen at the current front lines with referendums to be held in the seized territories on whether the residents there want to be part of Russia or Ukraine. Otherwise, she warned, Ukraine was certain to use the long-range weapons it was receiving from Western allies to hit Russian territory.

"This is already a certain revision of the official Russian position," the member of Russian diplomatic circles said.

But others cautioned that Simonyan's words represented no more than a fresh propaganda ploy by the Kremlin because any attempt to freeze the conflict at the current lines was only aimed at acquiring more time for the Russian army to rearm to attack again.

"Everyone in the Kremlin understands the danger of the Ukrainian counteroffensive," Stanovaya said. "Freezing the situation is very convenient, as this is exactly what will give Putin the time he needs for Ukraine and the West to lose their military zeal and unity."

Even as Russian border regions such as Belgorod have come under intensified shelling and drone attacks in recent days, the Kremlin has sought to downplay the impact of the incursions and has kept to a minimum any coverage of the attacks on state television. Still, resentment is bubbling up.

"How long will this go on!!! First, the border areas . . . now the outskirts of Belgorod," said one area resident in online comments. "We supported the Special Military Operation because we believed that it would push this evil spirits away from our borders, but the complete opposite has happened."

Another resident asked, "What does Putin think? What does he decide?"

The drone attacks in Moscow targeting plush residential compounds housing members of the Russian elite are starting to "impact people very seriously psychologically," one Russian businessman said, especially because in the capital, the war had until recently often seemed like no more than background noise. The spate of attacks could strengthen the position of hawks calling for martial law and the closure of Russia's borders, and increase squabbling among those seeking to secure their positions and wealth, he said.

Public tirades by Yevgeniy Prigozhin, the boss of the Wagner mercenary group and close Putin ally, against Russian army leadership for the failings of the war serve to "let off steam" and take place with Putin's permission because the criticism is channeled through someone who presents himself as a patriot, Stanovaya said.

But "at some moment," said Sergei Markov, a Kremlin-connected political consultant, infighting among factions in the elite around Putin "could spiral out of control."

The Kremlin is seeking to play down the cross-border attacks because it is aware that they probably are no more than an attempt by Kyiv to divert Russian troops from defending front-line positions, Markov said. Russia was instead focused on trying to defeat the Ukrainian counteroffensive and then seizing the opportunity presented by a weakened opponent to take more land, he said.

Russia is hoping the months it has had to prepare for Ukraine's counteroffensive will secure its positions. It has spent months building defensive positions and laying minefields, forcing the Ukrainian army to approach the front line "in columns," which so far have been easy to spot and target with artillery strikes, Markov said.

But unspoken behind that analysis, Markov said, is concern about a potential repeat of the issues that led to Russia's chaotic retreat around Kharkiv last fall, when poor management and inadequate communications between units led to "big problems" and crumbling Russian resolve.

The longer the war goes on, the more the conflict "is turning into a personal matter for Russians" and the harder it is becoming to contemplate any withdrawal of Russian forces, no matter how great the understanding is among the Russian elite that launching the invasion was a huge mistake, a Russian billionaire said.

"If your relative dies, you want to avenge his death. Nobody cares who started it," he said. "Everyone understands the war has not achieved its aims. But this is not going to influence the progress of the war. It is very difficult to stop. . . . Everything depends on the result of the counteroffensive."

Stanovaya largely agreed but said that while Putin, for now, is immunized by war fever and by the firm belief among most of the Moscow elite that Russia cannot lose because it has nuclear weapons, the course of the conflict could yet have unforeseen consequences for the president's standing.

"If Russia loses the corridor to Crimea, it will be a very serious blow," she said. "Everyone understands how important it is for Putin, and it will mean Putin has again not calculated the situation correctly and again not managed the situation. It will mean a very serious failure."