LONDON - Russia has been accused of taking its propaganda war to new heights after Moscow claimed Kyiv had tried to assassinate president Vladimir Putin in a drone strike targeting his residence in the Kremlin.

Ukrainian premier Volodymyr Zelensky vehemently denied the allegation, saying “we don’t attack Putin, or Moscow, we fight on our territory” as other Kyiv officials suggested Russia might be setting the scene for further escalation of the war as it threatened “retaliatory measures”.

As Kyiv prepares for a counteroffensive against Russian forces that Mr Zelensky said would be launched soon, Mr Putin’s presidential office said two drones were downed overnight, with the Russian leader having not been in the complex at the time. The RIA state news agency said Mr Putin spent Wednesday working at his Novo Ogaryovo residence outside Moscow.

A Kremlin statement said: “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 ... we regard these actions as a planned terrorist act and an attempt on the president’s life.”

Fragments of drones were scattered in the Kremlin grounds but there were no injuries or damage, it said.

Video posted by Baza, a Telegram channel with links to Russia's law enforcement agencies, showed a flying object approaching the dome of a Kremlin building overlooking Red Square, exploding in a burst of light just before reaching it.

Western allies of Ukraine cast doubt on the Russian claims. The US secretary of state, Antony Blinken, said he had seen the reports but that “anything coming out of the Kremlin” should be taken “with a very large shaker of salt” – adding that “we’ll see what the facts are”. Britain’s defence secretary, Ben Wallace, said that the UK would be assessing the reports of the drone strike, but that “I wouldn’t take at face value comments by Russia”.

Ukraine presidential adviser Mykhailo Podolyak suggested that the claims by Moscow would provide a pretext for Russia “to justify massive strikes on Ukrainian cities, on the civilian population, on infrastructure facilities” in the coming days.

Mark Galeotti, a prominent Russia analyst, said it was unlikely that the alleged attack had targeted Mr Putin, who “notoriously rarely goes to the Kremlin, let alone stays there overnight”. He tweeted that even if you were to assume it was an attack by Ukraine, it should be considered “a performative strike, a demonstration of capability and a declaration of intent: ‘don’t think Moscow is safe’”.

If the Kremlin’s comments were taken at face value, it would still raise serious questions about the security around Mr Putin, one of the most closely-guarded leaders in the world.

However, the incident certainly riled politicians in Moscow, who demanded action. Vyacheslav Volodin, the influential speaker of Russia’s parliament, demanded the use of “weapons capable of stopping and destroying the Kyiv terrorist regime” without specifying what those weapons would be.

Russian officials have repeatedly raised the spectre of possible use of nuclear weaponry during the invasion of Ukraine. Former president Dmitry Medvedev, a close Putin ally, said in a social media post that the alleged drone attack left Moscow with no options but to “eliminate” Mr Zelenskiy and his “clique” in Kyiv.

The Kremlin claimed the attack was planned to disrupt Victory Day, which Russia celebrates in Red Square on 9 May to commemorate the defeat of Nazi Germany in the Second World War. Moscow said the parade will take place as scheduled.

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. He offered no reason for the ban, saying only that it would prevent the “illegal use of drones that can hinder the work of law enforcement”.

Elsewhere, oil depots were ablaze in both southern Russia and Ukraine. Scores of firefighters battled a huge conflagration that Russian authorities claimed was a Ukrainian drone crashing into an oil terminal on Russia’s side of its bridge to Crimea. A fuel depot in Ukraine was ablaze after a suspected Russian drone strike on the central city of Kropyvnytskyi.

An administrative building in Ukraine's southern Dnipropetrovsk region was also hit by a drone and set ablaze. Ukraine said it had shot down 21 of 26 Iranian-made drones in an overnight volley, shielding targets in Kyiv where air raid sirens blared for hours through the night.

Sixteen people were killed by Russian shelling in Ukraine’s southern Kherson region, 12 of them in Kherson city, the Ukrainian prosecutor’s office said. Russian forces have regularly shelled the city from parts of Ukraine occupied by Russia.

Ukraine and Russia have both been carrying out long-range strikes since last week in apparent anticipation of the Ukrainian counteroffensive. Moscow says it has struck military targets, though it has produced no evidence to support this. Kyiv, without confirming any role in incidents in Russia or Crimea, said destroying infrastructure was preparation for its planned ground assault.

Meanwhile, Mr Zelensky visited Finland on Wednesday, his fourth known trip abroad since Russia’s full-scale invasion. Leaders of Denmark, Iceland, Norway and Sweden also attended his visit.

The president said his goals were to beef up Ukraine’s military and secure an eventual place in Nato, a goal endorsed by the five Nordic nations in a statement.

In Brussels, European Union countries finalised a scheme to jointly buy ammunition and missiles for Ukraine after weeks of talks.