The Kremlin on Wednesday accused Ukraine of a drone attack overnight in a foiled attempt to assassinate Russian leader Vladimir Putin, an allegation that could not be confirmed by independent sources.

Russian officials said Putin was not in the Kremlin at the time of the attack.

Ukraine said it had "nothing to do" with the attack. "Ukraine does not attack the Kremlin because, firstly, that does not solve any military aims," presidential spokesman Mikhaylo Podolyak said.

Analysts are concerned Russia could use the alleged attack to justify an increase in military action in its war in Ukraine.

What are the Kremlin's claims?

The Russian presidential office said in a statement it intercepted two drones sent to attack the Kremlin and that as "a result of timely actions taken by the military and special services with the use of radar warfare systems, the devices were put out of action."

The Kremlin did not provide evidence from the reported incident, and the statement with the accusations did not include details on the alleged attack.

There was also no immediate explanation for why it took over 12 hours to report the incident.

It added that Russia reserved the right to retaliate — suggesting that it could use the incident to justify an escalation in its war in Ukraine.

State news agency RIA reported that Putin was not in the Kremlin at the time, and was working on Wednesday at his Novo Ogaryovo residence outside Moscow.

A video circulating online appeared to show a flying object approaching the Kremlin and then exploding just before reaching one of the domes. The video was posted by a Telegram channel with links to Russia's law enforcement agencies. 

Another video posted online appeared to show a plume of smoke over the Kremlin. The videos could not be independently verified.

What has the response been?

Ukrainian officials denied the Russian accusations, with a senior advisor to Zelenskyy saying that the claims indicated Moscow was preparing a major "terrorist provocation."

The claims would likely provide a pretext for Russia "to justify massive strikes on Ukrainian cities, on the civilian population, on infrastructure facilities" in coming days, said presidential spokesman Podolyak.

Ukrainian President Volodymyr Zelenskyy also denied involvement, saying: "We don't attack Putin or Moscow. We fight on our territory. We're defending our villages and cities."

The United States said it is looking into Russia's claims. 

"We are still trying to validate this information," a US official told Reuters news agency, speaking on condition of anonymity. "If there was anything, there was no warning."

US Secretary of State Antony Blinken indicated that he was skeptical over the accusations, saying that "I would take anything coming out of the Kremlin with a very large shaker of salt."

Russia tightens security ahead of Victory Day parade

RIA said the Kremlin "assessed these actions as a planned terrorist act and an assassination attempt on the president on the eve of Victory Day, the May 9 parade."

Victory Day commemorates the Soviet Union's role in defeating Nazi Germany in World War II and is marked by a military parade in Moscow. Foreign dignitaries are expected to attend the event.

Shortly before the news about the alleged attack broke, Moscow Mayor Sergei Sobyanin issued a ban on using drones in the Russian capital, with an exception for drones launched by authorities.

Sobyanin didn't offer a reason for the ban, saying that it would prevent "the illegal use of drones that can hinder the work of law enforcement."

Moscow gains from alleged Kremlin attack, DW correspondent says

Moscow has a lot to gain from the alleged drone attack on the Kremlin, for which it has blamed Ukraine, said Jennifer Palke, DW's correspondent in Riga, Latvia.

Palke told DW that residents close to the Kremlin heard a noise which sounded like an explosion and saw a spark in the sky, before they saw "people with flashlights at the Krmelin walls."

"The Kremlin says as a result of timely actions taken by the military and special services the drones were rendered inoperable," Palke said.

She reminded, however, that the explosion was only reported by Russian media, with no Western media or experts yet able to verify it.

Ukrainians highly skeptical of claims

Alongside Kyiv's vehement denial of any involvement in the alleged Kremlin drone attack, DW's correspondent in Ukraine, Nick Connolly, said many in the capital are bracing for a potential increase in attacks.

Connolly added that some believed the attack was "a planned Russia false flag operation to justify further attacks on Ukraine or civilians in Ukraine." He reported an air raid warning across Ukraine, in anticipation of potential Russian retribution.

Connolly clarified the distinction between this alleged attack and previous Ukrainian drone attacks on Russia-controlled areas was that the latter attacks were on military and logistical targets.

He also noted that the locations of the attacks were much more accessible to Kyiv.

"Lots of images doing the rounds in recent months of anti-aircraft, anti-air defense units in Moscow on the roofs of office buildings in central Moscow," Connolly said. "So it's pretty extraordinary if it is true that Ukraine was able to launch weapons of this kind from Ukrainian territory and get them all the way to the walls of the Kremlin in the middle of Moscow.

rm/rs (Reuters, AP)