US intelligence sees no signs of Ukraine’s involvement in the Kremlin's attack

Mark Warner, chairman of the US Senate Intelligence Committee, told reporters after a closed-door briefing with CIA Director William Burns, CNN reports.

Warner says that the United States "still doesn't have a lot of information", but there is currently no indication that the source of the attack was Ukrainians. 

The US Institute for the Study of War (ISW) believes Russia probably organised the attack on the Kremlin itself.

Analysts suggest that Russia could have staged the attack to bring the war to a Russian domestic audience and create conditions for wider public mobilisation.

The ISW says the Russian authorities have recently allegedly taken steps to strengthen domestic air defence capabilities, including within Moscow itself.

"It is extremely unlikely that two drones could have penetrated multiple layers of air defences and exploded or been shot down right over the heart of the Kremlin in a manner that provided the spectacular images captured by the camera," the institute reports. 

The Kremlin's immediate, concerted and coordinated response to the incident may indicate that the attack was prepared domestically.