WASHINGTON (Dispatches) -- Russia has sent a formal letter to the U.S. warning that shipments of sensitive weapons from the United States and NATO were exacerbating tensions in Ukraine and could lead to “unpredictable consequences,” The Washington Post reported Friday.
The letter, which was viewed by The Post, added that the U.S. has flouted the rules governing the transfer of weapons to conflict zones.
According to the letter dated Tuesday, Russia accused NATO of impeding early peace negotiation with Ukraine “in order to continue the bloodshed”.
A State Department spokesperson confirmed that along with allies and partners, “we are providing Ukraine with billions of dollars worth of security assistance, which our Ukrainian partners are using to extraordinary effect to defend their country against Russia’s unprovoked aggression and horrific acts of violence”.
The news of the diplomatic letter comes as President Joe Biden announced an additional $800 million in military assistance to Ukraine this week, which for the first time included advanced munitions that the war-torn country has requested.
“The Ukrainian military has used the weapons we are providing to devastating effect. As Russia prepares to intensify its attack in the Donbas region, the United States will continue to provide Ukraine with the capabilities to defend itself,” Biden said.
The most recent round of U.S. security assistance includes a mixture of arms and other supplies that Washington has already provided Kyiv, as well as new capabilities that had not previously been sent over.
According to the Pentagon, the aid package includes 11 Mi-17 helicopters, 300 Switchblade drones, 200 M113 armored personnel carriers, 18 howitzers and 40,000 artillery rounds, 10 counter-artillery radars, 500 Javelin missiles, unmanned coastal defense vessels and protective equipment in the event of a chemical or biological weapons attack.
The president has also imposed a raft of sanctions on Russia in response to the “special military operation” in Ukraine.
The Russians have withdrawn forces from around the Ukrainian capital and are expected to focus attacks on the south and east, including the Donbas region.
The new report comes two days after Deputy Foreign Minister Sergei Ryabkov said Russia will view U.S. and NATO vehicles transporting weapons on Ukrainian territory as legitimate military targets.
Any attempts by the West to inflict significant damage on Russia’s military or its separatist allies in Ukraine will be “harshly suppressed,” he told the TASS news agency.
Russia said Friday it had struck a military target on the edge of Kiev with cruise missiles, promising more strikes against the Ukrainian capital.
Powerful explosions and air raid sirens were heard in the Ukrainian capital after Russia’s lead warship sank following a fire in the Black Sea.
The blasts appeared to be among the most significant in the country’s capital since Russian troops pulled back from the area earlier this month in preparation for battles in the south and east of Ukraine.
Russia’s defense ministry said its forces had also completely taken control of the Ilyich Steel Plant in the besieged port city of Mariupol.
On Wednesday, Moscow said 1,026 soldiers of Ukraine’s 36th Marine Brigade, including 162 officers, had surrendered near the steel plant.
Mariupol has been encircled by Russian troops for weeks. It has seen the fiercest fighting and the most comprehensive destruction since Russia launched a military operation in Ukraine on Feb. 24.
Russia’s new strikes came after its Black Sea flagship, the Moskva missile cruiser, sank after being seriously damaged in an explosion and fire. Ukraine claimed responsibility for what it termed a “successful missile strike”, using a locally-made Neptune anti-ship missile.
Russia’s defense ministry said the Soviet-era vessel sank late on Thursday as it was being towed to port.
The ship reportedly could carry 16 long-range cruise missiles, and its loss would greatly reduce Russia’s firepower in the Black Sea.
Ukraine’s President Volodymyr Zelensky referred to it in an early

morning video address in which he warned of Russian intentions to target the eastern Donbas region, including Mariupol.
As the raging conflict entered its 51st day, several parts of the country continued to be bombed.
According to the UN, approximately 4.736 million Ukrainians have fled their country. The vast majority of those displaced people – some 2.6 million – have sought refuge in neighboring Poland.
The Russian defense ministry said Friday its strategic rocket forces “eliminated up to 30 Polish mercenaries” in a strike on the village of Izyumskoe, not far from the city of Kharkiv.
Canada said it was sending 150 military personnel to Poland to assist Polish authorities with processing and resettling millions of Ukrainian refugees fleeing the war.
Poland’s foreign minister said the eastern flank of NATO needed stronger defense after Biden spoke to leaders from the region about security.
One of Putin’s closest allies warned that if Sweden and Finland joined the NATO military alliance, Russia would deploy nuclear weapons and hypersonic missiles in an exclave in the heart of Europe.
Russia possesses the world’s largest arsenal of nuclear warheads and, along with China and the United States, is one of the global leaders in hypersonic missile technology.
CIA Director William Burns said on Thursday that Russia’s threat to potentially use tactical or low-yield nuclear weapons in Ukraine cannot be taken lightly.
The CIA, however, has not seen a lot of practical evidence reinforcing that concern, Burns added.
Burns spoke at Georgia Tech of what he alleged as “potential desperation” and setbacks dealt to President Putin.
For those reasons, he said, “none of us can take lightly the threat posed by a potential resort to tactical nuclear weapons or low-yield nuclear weapons”.
Tactical and low-yield nuclear weapons refer to those designed for use on the battlefield, of which some experts estimate Russia has about 2,000 that can be delivered by air, naval and ground forces.
The CIA director also accused China of being “a silent partner” in Russia’s “aggression” in Ukraine.
Burns said China posed the “greatest challenge” and “most profound test” the agency had ever had to deal with, as he marked his first year in charge of the spy agency.