The United States has rejected Russia's demand to halt further NATO expansion eastward, but offered what it called a "serious diplomatic path" to resolve a heated confrontation between Moscow and the West amid a Russian military buildup near Ukraine.
Washington handed over its written response to Russia's security demands on January 26, which U.S. Secretary of State Antony Blinken described as a "principled and pragmatic" evaluation of the concerns that Moscow has raised.
Blinken late on January 26 also spoke to Chinese Foreign Minister Wang Yi about Ukraine, highlighting the global security and economic risks that could stem from further Russian aggression, the State Department said.
Russia has amassed more than 100,000 troops, according to Western intelligence, near the border with Ukraine and has been holding a series of land and sea military exercises, sparking concern it may be preparing for a further incursion into the country after illegally annexing Crimea from Ukraine in 2014.
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Moscow is also backing separatist fighters in an ongoing war in eastern Ukraine that has claimed more than 13,200 lives since April 2014.
The Kremlin, which denies planning to enter Ukraine, has said it sees NATO as a security threat, and is demanding legal guarantees that the Western military alliance will not further expand eastward, including to neighboring Ukraine.
Washington and NATO have said some of the demands are nonstarters.
Blinken told reporters the United States was open to dialogue, but made it "clear that there are core principles that we are committed to uphold and defend, including Ukraine's sovereignty and territorial integrity, and the right of states to choose their own security arrangements and alliances."
"There is no change; there will be no change," he said.
Blinken said the letter was fully coordinated with Ukraine and Washington's European allies and "sets out a serious diplomatic path forward, should Russia choose it," as the United States seeks to avert a military escalation against Ukraine.
But he warned Washington was acting "with equal focus" to bolster Ukraine's defense.
He said he would speak to Russian Foreign Minister Sergei Lavrov in the coming days for Moscow's response to the U.S. stance.
During his call with Chinese counterpart Wang, Blinken underlined the need for de-escalation, State Department spokesman Ned Price said in a statement. "Secretary Blinken...conveyed that de-escalation and diplomacy are the responsible way forward," Price said.
Wang for his part called for calm in the Ukrainian crisis, the Chinese Foreign Ministry said in a statement. "We call on all parties to stay calm and refrain from doing things that agitate tensions and hype up the crisis," the statement said.
China and Russia have been stepping up their ties amid tension between Beijing and Washington over a range of issues, from trade to human rights, Taiwan, Hong Kong, and China's maritime claims.
NATO also sent its written response to Russia's demands to Moscow, which Secretary-General Jens Stoltenberg said included proposals for a diplomatic solution to the crisis.
Stoltenberg called on Russia to "immediately de-escalate the situation," but said NATO allies remained "prepared for the worst."
"We see more troops not only in and around Ukraine, but also now in Belarus, where Russia is in the process of deploying thousands of troops, hundreds of aircraft, S-400 air defense systems and a lot of other very advanced capabilities," he said, adding this was happening under the disguise of an exercise.
Russia says the crisis is being driven by NATO and the United States, accusing them of "escalating tensions." Although Russia denies it is planning an attack, it kicked off military drills near Ukraine on January 25 involving thousands of troops and dozens of warplanes.
After attending diplomatic talks in Paris between Russia, Ukraine, Germany, and France, Kremlin envoy Dmitry Kozak reiterated Moscow's view that Western calls for Moscow to deescalate by halting troop movements on its own territory are pointless.
In earlier remarks to the State Duma, Lavrov repeated Moscow's threat that if the West does not respond to its demands, Russia will take unspecified "appropriate measures."
U.S. President Joe Biden issued a rare threat on January 25, saying that he would consider personal sanctions on his Russian counterpart, Vladimir Putin, in case of an invasion of Ukraine.
British Foreign Secretary Liz Truss said on January 26 that her country was "not ruling anything out" when asked if the United Kingdom would consider a similar move.
Kremlin spokesman Dmitry Peskov told reporters in Moscow that individual sanctions against Putin would be "not painful [but] politically destructive," noting Russia's top leaders are legally barred from holding assets, property and bank accounts abroad.
On January 25, additional U.S. military hardware arrived in Kyiv -- including Javelin anti-tank missiles and launchers -- the third installment of a $200 million package to shore up Ukraine's defenses.
Truss said Britain was also supplying defensive weapons to Ukraine.
The Czech Defense Ministry said it would donate 4,000 artillery shells, worth $1.7 million to Ukraine in the next few days.
Germany, which has refused to provide weapons to Ukraine, offered to send 5,000 helmets.
Biden consulted with allied European leaders earlier this week over the tensions caused by Russia's troop buildup, and the Pentagon announced it was putting up to 8,500 U.S. soldiers on "heightened alert" for potential deployment to bolster NATO's presence in the region.
Biden said he had "no intention" of sending U.S. troops into Ukraine but again warned Russia of severe sanctions if Moscow orders an attack.
NATO has about 4,000 troops in multinational battalions in Estonia, Lithuania, Latvia, and Poland. They are backed by tanks, air defenses, and intelligence and surveillance units.
Romanian President Klaus Iohannis said his country was in talks with France and the United States on increasing the number of NATO troops it hosts.
"I have no idea whether [Putin's] made the ultimate decision, but we certainly see every indication that he is going to use military force sometime perhaps [between] now and the middle of February," U.S. Deputy Secretary of State Wendy Sherman told an online forum on January 26.
Meanwhile, the U.S. Embassy in Kyiv issued an alert urging Americans in Ukraine to considering leaving the country given the "unpredictable" situation.
"The security situation in Ukraine continues to be unpredictable due to the increased threat of Russian military action and can deteriorate with little notice," the embassy said in a statement on January 26.
As part of a continuing diplomatic effort, advisers to the leaders of Russia, Ukraine, France, and Germany met in Paris, and reaffirmed in a joint statement their commitment to uphold a cease-fire agreed in the Minsk accords aimed at putting an end to the conflict in eastern Ukraine.
Although there was no breakthrough in the talks, held under the so-called Normandy format, they promised to meet for new talks in two weeks in Berlin.
Meanwhile, Ukrainian Foreign Minister Dmytro Kuleba told a briefing on January 26 that Ukraine had no objections to responses the United States will send to Russia as part of negotiations to avert a military escalation.
"We know very well what our partners will tell Russia. We are aware of all of that and everything has been coordinated with us," Kuleba said.
As part of a continuing diplomatic effort, French President Emmanuel Macron has scheduled a phone call with Putin for January 28 in which he is expected to seek clarification over Russia's intentions.
A top Ukrainian official on January 26 ruled out the prospect of Kyiv holding direct talks with Kremlin-backed separatists and said that major cease-fire violations were happening in the conflict in eastern Ukraine.
"There have not been and will not be any direct talks with the separatists," said Andriy Yermak, chief of staff to President Volodymyr Zelenskiy, in a statement on Facebook.
Kuleba accused Russia of trying to sow panic in Ukraine.
He also said Moscow had not massed enough troops for a large-scale offensive against Ukraine, but added that did not mean it could not do so later on.