The US is gathering facts of an alleged drone attack by Ukraine on the Kremlin

According to an unnamed American official, the United States was not warned about the alleged drone attack on the Kremlin.

"Whatever happened, there was no advanced warning," the US official told CNN, adding that authorities are still trying to figure out what exactly happened.

Another US official told CNN they are still working to assess Russia's claims and have not yet validated the Kremlin assertion that Ukraine tried to assassinate Putin.

Earlier, the press service of the Kremlin claimed that Ukrainian unmanned aerial vehicles "attempted to launch an attack" on "the Kremlin residence of Vladimir Putin, the President of Russia."

Serhii Nykyforov, spokesman for President Volodymyr Zelenskyy, has said that Ukraine has no information about last night’s attack on the Kremlin.