“The Embassy, as always, recommends U.S. citizens be prepared to immediately shelter in the event an air alert is announced.”

A similar warning was issued on November 20 last year, one day before Russia struck Dnipro with an Oreshnik intermediate-range ballistic missile (IRBM).

It is also known that Russia has announced in a new NOTAM alert that it is closing airspace over its Kapustin Yar missile test site in Astrakhan region between 6:00 a.m. on May 12 and 6am, May 13.

It was from this test site that it launched an Oreshnik on Dnipro.

Any new Russian strike on Ukraine will jeopardise a major new effort from the US and European states including Britain to force Putin to agree a 30-day unconditional ceasefire starting immediately creating a window for a full peace agreement to end the debilitating war.

It remains deeply doubtful that Putin - who staged a massive military parade in Moscow on Friday - has any intention of halting the war.

But Merz expressed optimism that an agreement can be reached rapidly amid a threat of huge new sanctions on Russia if Putin continues the war.

“I have great hope that a ceasefire agreement in Ukraine will be reached this weekend,” he said.

“Now the ball is in Moscow's court.”

Donald Trump demanded: “I have a message to both sides: end this war.

“We are losing 5,000 soldiers a week, Russian and Ukrainian soldiers, and other people, and I say: end this stupid war. This is my message to both sides.”

The Kremlin dictator’s spokesman, Dmitry Peskov, appeared to obfuscate, telling ABC News that Putin demanded “certain dynamics” on the battlefield before agreeing on an extended ceasefire - notably a halt to Western military supplies to Kyiv, a move that would leave Ukraine open to further invasion by Russia.

“Otherwise, it will be [advantageous] for Ukraine,” Peskov alleged.

“Ukraine will continue their total mobilisation, bringing new troops to the front line.

“Ukraine will use this period to train new military personnel and to give a rest to their existing ones…

“So why should we grant such an advantage to Ukraine?”

Despite Kyiv insisting it is ready for an immediate month-long truce and talks with Moscow, Peskov alleged Kyiv was “not ready for immediate negotiations”.

Denying the Kremlin was dragging its feet, he claimed: “President Putin is doing whatever is possible to solve the problem, to achieve a settlement through peaceful and diplomatic means. But having no peaceful and democratic means at hand, we have to continue [the] military operation.”

Trump has demanded “ideally, a 30-day unconditional ceasefire.

“Hopefully, an acceptable ceasefire will be observed, and both Countries will be held accountable for respecting the sanctity of these direct negotiations”.

The European leaders - including Starmer - said in a statement before arriving in Kyiv: “The bloodshed must end, Russia must end its illegal invasion, and Ukraine must be allowed to flourish as a secure and independent nation within its internationally recognised borders for generations to come.

“We intend to continue to increase our support for Ukraine.

“We will increase pressure on the Russian war machine until Russia agrees to a permanent ceasefire.”

The leaders vowed to assure Zelensky of their unwavering commitment to Ukraine.

“We, the leaders of France, Germany, Poland and Britain, stand in Kyiv in solidarity with Ukraine against Russia's barbaric and illegal full-scale invasion.”

Three civilians were killed in Ukraine’s Sumy region in Russian strikes on May 8 and 9 despite Putin’s ceasefire.

Putin’s obedient media has warned in recent days that Putin had given the go-ahead to a new Oreshnik strike.

Kremlin-friendly Mash news outlet reported three days ago:“Vladimir Putin gave the Russian Defence Ministry instructions to identify targets in Kyiv for the Oreshnik strike.”

A similar report was carried by Baza, also close to the Kremlin.

Oreshnik is nuclear-capable, but Putin threatens that it is almost as destructive with non-nuclear warheads.

Targets would be incinerated, he said, with warheads unleashing a temperature of 4,000 °c, almost as hot as the surface of the sun.

Russia hit the Ukrainian city of Dnipro with a fearsome medium-range ballistic Oreshnik missile in November 2024 in response to the use of UK and US missiles against its territory in what was widely seen as a revenge attack.

Yet it was also seen as a test combat launch without a live warhead - sent as a warning of the Armageddon that could follow.

Last year’s launch was accompanied by a barrage of threats from Putin to re-use it with doomsday consequences unless the West stopped allowing Ukraine to hit Russian territory with NATO missiles.