Vladimir Putin has unleashed a "new intercontinental ballistic missile" in a show of strength to the West as US President Joe Biden visits Europe.
The Russian leader debuted the new weapon in a test launch overnight, allegedly "successfully" striking a target at a firing range in Kazakhstan.
But full details of the rocket were not released and experts have speculated it is the powerful Topol-Me system.
It was fired from the Kapustrin Yar test site in Astrakhan region and hit the Sary-Shagan range in neighbouring Kazakhstan.
But Russia has long had issues in turning test launches and bold promises of new, game-changing missiles into weapons they have actually been able to use on the battlefield.
The hypersonic Sarmat rocket, known in the West as Satan-2, has long been subject to humiliating delays in getting it war-ready and the former Putin ally who led the programme was discretely let go, after failures to make good on his many promises.
The new weapon comes as Russia continues its ongoing war with Ukraine, and as US President Joe Biden landed in Northern Ireland.
In an official statement, the Russian defence ministry claimed: “The combat crew of the Strategic Missile Troops successfully launched a intercontinental ballistic missile of the land-based mobile missile system from the Kapustin Yar State Central Training Ground in the Astrakhan Region.”
The launch was aimed at “testing the advanced military supply of intercontinental ballistic missiles”, reported TASS citing the ministry.
“The launch permitted proving that design and engineering solutions used in the development of new strategic missile complexes are correct,” said the ministry.
Russia is also due to carry out more tests with its big beast Satan-2 rockets, which appears subject to more delays after a failure to meet a deployment deadline at the end of 2022.
Some reports have suggested a failed test launch of Sarmat in February.
The Satan-2 rocket is the size of a 14 storey tower block weighing 208 tons which, in theory, is capable of delivering multiple nuclear warheads.
Five test launches of Satan-2 have been predicted for this year but it is unknown whether these will actually go ahead.
In May last year, former head of Roscosmos Dmitry Rogozin, seen as a close Putin ally, claimed that almost 50 Satan-2 missiles, which were in mass production, would soon be on combat duty.
Then in early June, a major ICBM test was scheduled and locals near the Kura test range were warned to stay clear of the target site in remote Kamchatka.
But this test never happened.
On 25 June Rogozin boasted: "We are absolutely on schedule, we are now preparing for the second flight test of the Sarmat.”
The following month Rogozin was fired for unknown reasons with his promised new job yet to arrive.
His successor, ex-deputy premier Yury Borisov, in July repeated the claim that the missile is in mass production without reiterating Putin’s goal of Satan-2 being on combat duty by December.
