Russia accused the United States on Thursday of being behind what it says was a drone attack on Moscow’s Kremlin citadel intended to kill President Vladimir Putin.

A day after blaming Ukraine for what it called a terrorist attack, the Kremlin administration shifted the focus onto the United States, but without providing evidence to support its accusation.

Ukraine has denied involvement in the incident in the early hours of Wednesday, when video footage showed two flying objects approaching the Senate Palace inside the Kremlin walls and one exploding with a bright flash.

“Attempts to disown this, both in Kyiv and in Washington, are, of course, absolutely ridiculous. We know very well that decisions about such actions, about such terrorist attacks, are made not in Kyiv but in Washington,” said Putin’s spokesman Dmitry Peskov.

He said the United States was “undoubtedly” behind the alleged attack and added - again without stating evidence - that Washington often selected both the targets for Ukraine to attack, and the means to attack them.

“This is also often dictated from across the ocean. We know this well and are aware of this ... In Washington they must clearly understand that we know this.”

Russia has said with increasing frequency that it sees the United States as a direct participant in the Ukraine war, intent on inflicting a “strategic defeat” on Moscow. The United States denies that, saying it is arming Ukraine to defend itself against Russia’s

invasion and retake territory that Moscow has seized illegally in more than 14 months of war.

Calls to kill Zelenskiy

However, Peskov’s allegation that the United States was behind a plot to kill Putin went further than previous Kremlin accusations against Washington.

Putin was not in the Kremlin at the time, and security analysts have poured scorn on the idea that the incident was a serious assassination attempt.

But Russia has said it reserves the right to retaliate, and hardliners including former president Dmitry Medvedev have said it should now “physically eliminate” Ukrainian President Volodymyr Zelenskiy.

Peskov declined to say whether Russia saw Zelenskiy as a legitimate target.

He said Russia had an array of options and the response, when it came, would be carefully considered and balanced. He said an urgent investigation was under way, but could not say when the results would be known.

Putin was in the Kremlin on Thursday and staff were working normally, he said.

The incident took place less than a week before Russia’s May 9 Victory Day celebrations marking the defeat of Nazi Germany in World War Two - an important public holiday and an opportunity for Putin to rally Russians behind what he calls Russia’s “special military operation” in Ukraine.

Peskov said air defences would be tightened, and this was happening anyway for the military parade on Red Square, the centrepiece of the holiday, just over the Kremlin wall from the site of the alleged attack.

He said the parade would go ahead as normal, and include a speech from the president.