Russia, angered over what it says are "unprecedented" and "provocative" statements from the West, threatened retaliatory moves "inside Ukraine and beyond," as well as plans to conduct military exercises with tactical nuclear weapons that the European Union called "irresponsible."
Since Moscow launched its full-scale invasion of Ukraine in February 2022, relations between Russia and the West have deteriorated to their lowest level since the end of the Cold War, with Kyiv's Western allies throwing their support behind Ukraine's struggle to repel overwhelmingly superior Russian forces.
In the latest moves, Moscow on May 6 blasted remarks by U.K. Foreign Secretary David Cameron, who said Ukraine "has the right" to launch attacks inside Russia with British-made weapons, and it called remarks by President Emmanuel Macron suggesting that Paris could eventually send troops to Ukraine to assist Kyiv in its battle against Russia's full-scale invasion "irresponsible and mindless."
The Western allies "are deliberately leading the situation toward a further escalation of the Ukrainian crisis toward an open military clash between NATO countries and Russia," Russia’s Foreign Ministry said in a statement.
The ministry said it summoned British Ambassador Nigel Casey over Cameron's remarks, "firmly pointing out that Cameron's hostile move directly contradicts the previously sounded assurances of the British side while transferring long-range cruise missiles to the Kyiv regime, that under no circumstances would they be used on the Russian territory."
SEE ALSO: Moscow Summons British Envoy Over Cameron's 'Hostile' Remarks On Attacks Inside RussiaIt said Cameron's remarks meant he was "de facto recognizing his country as a party in the conflict" and that any use of British weapons on Russian territory could make targets of "any British military facilities and equipment on the territory of Ukraine and beyond."
In a separate statement, the ministry blasted remarks by Macron on potential use of French troops inside Ukraine, saying it found them "amusing for their irresponsibility and thoughtlessness."
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"It is difficult to perceive all this other than as a statement about the readiness and intention to enter into direct armed confrontation with Russia, which would mean a head-on military clash of nuclear powers," it added.
Hours earlier, Russia announced plans to conduct military exercises to ensure its readiness to use tactical nuclear weapons.
The announcement by the Defense Ministry is the first time Russia has publicly announced drills involving tactical nuclear weapons.
A European Commission spokesman assailed the Russian announcement, labeling it "saber-rattling" and a "continuation of Russia's irresponsible behavior."
A spokesman for EU foreign policy chief Josep Borrell said the move was further "proof that the Kremlin is only interested in further escalating the situation which was caused by its illegal aggression against Ukraine."
Washington called the nuclear remarks "irresponsible rhetoric."
"This is an example of the kind of irresponsible rhetoric we've seen from Russia in the past. It's completely inappropriate given the current security situation," Pentagon spokesman Major General Pat Ryder said.
"We've not seen any change in their strategic force posture.... Obviously, we'll continue to monitor," he added.
The role of strategic nuclear weapons is to strike enemy targets far from the front line, while tactical nuclear weapons are designed to be used on battlefields.
The exercise is meant to increase the ability of Russia's military to "ensure the territorial integrity and sovereignty of the Russian state in response to provocative statements and threats of individual Western officials against the Russian Federation," the statement said, without elaborating.
Kremlin spokesman Dmitry Peskov, when asked by journalists what had prompted the announcement on nuclear readiness, said, "It's obvious we are talking about statements from Mr. Macron and statements from British representatives,"
"This is a completely new round of escalating tensions. It is unprecedented and requires special measures," Peskov said.
Separately, the governor of Russia's Belgorod region bordering Ukraine said on Telegram that seven people were killed and 42 wounded by Ukrainian drones near Berezovka, in the Borisov district close to the Ukrainian frontier, when two buses carrying workers to a pig farm were struck by Ukrainian drones.
Ukraine has not commented on the claim, which could not be independently confirmed.
Ukraine has been subjected to almost daily Russian missile and drone strikes that have caused huge damage to its civilian and energy infrastructure and killed and wounded numerous civilians, including children.
In response, Kyiv has targeted energy infrastructure inside Russia, especially oil refining installations.
Russia on May 6 said its forces had taken control of the settlements of Solovyove in Ukraine's eastern Donetsk region and Kotlyarivka in the Kharkiv region.
Ukrainian authorities did not acknowledge the potential loss of the settlements, but many Ukrainian bloggers appeared to confirm that both had been taken by Russia.
Earlier the Ukrainian Air Force said it had downed 12 out of 13 drones launched by Russia at energy infrastructure targets in the Sumy region. The regional administration said the electricity supply was temporarily cut in Sumy, Romniy, and Okhtyrka.