Russia just used its new hypersonic missile again in Ukraine. Here's what to know about the Oreshnik

Russia said Friday it used its latest missile against Ukraine for a second time in the nearly 4-year-old war, a forceful signal to Kyiv and its Western allies as U.S.-led peace talks have entered a new and crucial stage.

The hypersonic Oreshnik intermediate range ballistic missile hit Ukraine's western Lviv region late Thursday night, although officials there did not mention any casualties. The area is near a military base in neighboring Poland, a NATO member, that serves as a key hub for ferrying Western military supplies to Kyiv.

Some Moscow commentators said the attack was a warning to European leaders against proposals to deploy their troops to Ukraine as part of a prospective peace deal. Russia has said it won't accept such a deployment and would view those forces as legitimate targets.

A look at the weapon and why Russia used it now:

What's known about the Oreshnik

Russia first used the multiple-warhead Oreshnik on the Ukrainian city of Dnipro in November 2024.

President Vladimir Putin said the Oreshnik, which means ''hazelnut tree'' in Russian, streaks at 10 times the speed of sound, or Mach 10, ''like a meteorite,'' and was immune to any missile defense system.

The Russian military said the Oreshnik can carry nuclear or conventional warheads and can reach any European target.

The Pentagon said the Oreshnik was an experimental type of intermediate-range ballistic missile, or IRBM, based on Russia's RS-26 Rubezh intercontinental ballistic missile, or ICBM. Intermediate-range missiles can fly between 500 to 5,500 kilometers (310 to 3,400 miles). Such weapons were banned under a Soviet-era treaty that Washington and Moscow abandoned in 2019.

When Russia first used the Oreshnik, Ukraine's military said the missile had six independently targetable warheads, each carrying six submunitions.

Russian military bloggers said the submunitions released by each warhead apparently were unarmed but had high kinetic energy estimated to deliver a destructive force equivalent to tons of explosives.

Since the start of its full-scale invasion of Ukraine in 2022, Russia has used swarms of cheap slow-flying drones and an assortment of other missiles, but none had the range and power of Oreshnik.

Russia's Defense Ministry said last month the Oreshnik had been deployed to Belarus and entered active service. It didn't specify how many missiles were sent to the key ally of Moscow and whether they were fitted with nuclear warheads, but Belarusian President Alexander Lukashenko said that up to 10 Oreshnik systems will be stationed there.

Russia previously has stationed tactical nuclear weapons inside Belarus, whose territory it used to launch the invasion of Ukraine.

In 2024, Putin released a revised nuclear doctrine that placed Belarus under Russia's atomic umbrella. The document significantly lowered the threshold for the possible use of nuclear weapons, declaring that any nation's conventional attack on Russia that is supported by a nuclear power will be considered a joint attack on the country. The threat was clearly aimed at discouraging the West from allowing Ukraine to strike Russia with longer-range weapons.

Unlike Russia's other shorter-range conventional weapons, the Oreshnik is able to launch a powerful, conventional strike anywhere in Europe, giving the Kremlin a new instrument of escalation without tapping its nuclear arsenal. There will be no way to know whether the missile is carrying a nuclear or a conventional warhead before it hits the target.

Russia's message by using the Oreshnik

Its latest strike comes as the U.S.-led efforts to end the war in Ukraine have entered a pivotal stage and appears to underline Putin's intention to negotiate from a position of strength as his troops make slow but steady territorial gains.

Some Russian military bloggers noted that the strike in Lviv, not far from the Polish border, was a message intended for Kyiv's allies. Those members of the ''coalition of the willing'' have proposed sending their troops to Ukraine as part of security guarantees once a peace deal is reached.

Russia has said it won't accept any European forces in Ukraine, seeing them as legitimate targets.

''For the first time, NATO command has been shown a strategic weapons strike virtually on its border,'' said military expert Valery Shiryayev. ''This action is intended to demonstrate the determination of Russia's military and political leadership to use such weapons with nuclear warheads if necessary.''