A new "experimental" Russian missile travelled at over 11 times the speed of sound — or over 13,000 kilometres per hour — before hitting targets in the Ukrainian city of Dnipro, Kyiv's top spy agency says.

Russian President Vladimir Putin confirmed the military had launched the new medium-range hypersonic ballistic missile weapon, known as "Oreshnik", on Thursday morning. 

Ukraine's Main Directorate of Intelligence (HUR) said in a statement on Friday it believed the missile had reached Mach 11 by the time it had reached its target.

"The missile was equipped with six warheads: each equipped with six submunitions," HUD said.

"The flight time of this Russian missile from the moment of its launch in the Astrakhan region to its impact in the city of Dnipro was 15 minutes."

Ukraine's government initially said Dnipro had been struck by a non-nuclear intercontinental ballistic missile, which would have represented a major escalation in the conflict.

However, Mr Putin as well as NATO and US sources later said the weapon was an intermediate-range ballistic missile.

Mr Putin said the missile travelled at such a speed that it could not be intercepted by air defences.

Experts say it is possible for the weapon to be fitted with nuclear warheads, however on Thursday it was equipped with conventional explosives.

Ukraine's parliament cancelled its sittings on Friday over fears of a Russian missile attack on Kyiv's government buildings.

The day before Russia's use of the new weapon, several foreign embassies — including the US embassy — were temporarily closed.

NATO will hold an emergency meeting with Ukraine at the alliance's headquarters in Brussels on Tuesday to discuss Moscow's strike, a NATO source told Reuters on Friday.

Oreshnik's launch follows Ukraine's reported use of UK and US-supplied missile systems inside Russia, which until recently had been blocked by Western allies.

Mr Putin said on Thursday the use of American and British weapons gave the conflict a "global nature".

German Chancellor Olaf Scholz described Russia's strike as a "terrible escalation".

Unlike the US or UK Germany's government has not approved the use of its weapons by Kyiv inside Russian territory.

Kremlin spokesperson Dmitry Peskov said on Friday the Oreshnik launch was a clear warning to the West that Moscow would respond to countries that allowed Ukraine to use weapons on Russian targets.

Mr Peskov said Russian authorities had informed the US of its intention to launch the intermediate-range missile 30 minutes ahead of time.

Reuters/AFP