US soldiers arrived in Poland on Saturday as part of NATO moves to send in extra troops over fears that Russia could invade Ukraine, a Polish army spokesman told AFP.

"The first batch has arrived at the airport in Jasionka" in southwestern Poland, Major Przemyslaw Lipczynski said, adding that the bulk of a contingent of 1,700 US soldiers would follow "soon".

He said the soldiers who arrived Saturday were from the 82nd Airborne Division.

"Our Corps’ presence serves to bolster existing US forces in Europe and demonstrates our commitment to our NATO Allies and Partners,” added Captain Matt Visser, spokesman for the 18th Airborne Corps, which includes the 82nd division.

The corps was made up of "combat-capable forces who stand ready to enhance the Alliance’s ability to deter and defeat Russian aggression," the US statement added.

Washington said last week it would send about 3,000 additional troops to eastern Europe to defend NATO members against any "aggression".

Washington is sending 2,000 troops stationed in the US. They are being flown to Germany and Poland. Another 1,000 already in Germany are being sent to Romania. 

Western capitals have accused Russia of amassing 100,000 troops on the borders of pro-Western Ukraine in preparation for an invasion and have vowed to impose devastating sanctions on Moscow if it attacks.

Putin wins Xi backing

Russia won China's backing in its showdown with the West over Ukraine on Friday, as Beijing agreed with Moscow that the US-led NATO military alliance should not admit new members.

The demand for NATO to stop expanding came after a meeting between Russian President Vladimir Putin and Chinese counterpart Xi Jinping in Beijing that saw Putin hail the two countries' "dignified relationship".

In a long strategy document, Moscow and Beijing hit out at what they said was Washington's destabilising role in global security.

"The parties oppose the further expansion of NATO and call on the North Atlantic Alliance to abandon the ideological approaches of the Cold War era," the document read, urging respect for the "sovereignty, security and interests of other countries." 

The call echoes demands from Russia that have been at the centre of weeks of intensive negotiations between Moscow and the West, under the shadow of a potential conflict.

NATO Secretary General Jens Stoltenberg hit back at the Russo-Chinese claims. 

"This is fundamentally not about NATO expansion. This is about respecting the right of every sovereign nation to choose their own path," he told MSNBC's Morning Joe. 

Western capitals have accused Russia of amassing some 100,000 troops on the borders of pro-Western Ukraine in preparation for an invasion and have vowed to impose devastating sanctions on Moscow if it attacks.

The document released by Beijing and Moscow Friday also set out criticisms of Washington's "negative impact on peace and stability" in the Asia-Pacific region.

Russia and China also said they were "seriously concerned" by the AUKUS defence alliance including Australia, the UK and the United States.

German Chancellor Olaf Scholz was the latest European leader to announce a visit to the region on Friday, saying he would go to Ukraine on February 14 and Russia the next day.

Later Friday, the first US soldiers of the 3,000 announced by President Joe Biden this week arrived in Germany at the Wiesbaden military base.

The US is sending 2,000 troops stationed in the US. They are being flown to Germany and Poland. Another 1,000 already in Germany are being sent to Romania.

- 'Delusional' false flag claims -
French President Emmanuel Macron will visit Moscow on Monday and Kyiv on Tuesday for talks with his Russian and Ukrainian counterparts.

Putin's meeting with Xi -- hours ahead of the opening ceremony of the Winter Olympic Games -- came after the United States said it had evidence of a plan by Moscow to film a fake Ukrainian attack on Russians to justify an attack on its neighbour.

Pentagon spokesperson John Kirby said the US had "information that the Russians are likely to want to fabricate a pretext for an invasion", but did not provide evidence.

Russia, which has repeatedly denied any invasion plans, said the US claims were absurd.

"The delusional nature of such fabrications -- and there are more and more of them every day -- is obvious," Foreign Minister Sergei Lavrov said.  

Washington's claim came on the back of visits from European leaders to shore up their backing for Kyiv, including from British Prime Minister Boris Johnson and Turkish President Recep Tayyip Erdogan. 

Ukraine's Foreign Minister Dmytro Kuleba on Friday welcomed the displays of support, saying they had prevented Russia from "further aggravating the security situation".

- 'Intimidation strategy' -
"Our partners believe in Ukraine and that means Moscow's intimidation strategy is not working. Russia has lost this round," Kuleba said.

During Erdogan's visit Thursday he and Ukrainian President Volodymyr Zelensky signed an agreement expanding the production of parts in Ukraine for a Turkish combat drone whose sale to Kyiv has angered Moscow.

Erdogan has tried to position Turkey, which is a member of NATO, as a neutral mediator close to both Moscow and Kyiv.

Following his trip, Erdogan accused the West of making the crisis "worse".

"Unfortunately, the West until now has not made any contribution to resolving this issue," he said in comments published by local media Friday.

"They are only making things worse," Erdogan said, adding that Joe Biden "has not yet been able to demonstrate a positive approach".

Russia's relationship with the West was severely damaged in 2014 when it annexed the Crimean peninsula from Ukraine and threw its political weight behind armed separatists in the east the country.

Nearly eight years of fighting between Kyiv and the pro-Moscow fighters have cost more than 13,000 lives and seen the West and Russia exchange waves of tit-for-tat sanctions.

In the most recent diplomatic flare-up, Putin has demanded guarantees that Ukraine will not join NATO and has implicitly threatened the former Soviet state with the massive military build-up.

Russia also wants NATO and the United States to foreswear the deployment of missile systems near Russia's borders and to pull back NATO forces in eastern Europe.

These tensions have been aggravated by plans for joint military exercises between Russia and neighbouring Belarus, where Washington claims Moscow is preparing to send 30,000 troops.

Russia preparing full-scale invasion

Russia has stepped up preparations for an all-out invasion of Ukraine but it is not clear if Moscow has decided to take such a step, US officials have said citing intelligence assessments.

Russia has assembled 110,000 troops along the border with its pro-Western neighbor but US intelligence has not determined if President Vladimir Putin has actually decided to invade, according to the officials who in recent days briefed members of Congress and European allies.

The officials warned lawmakers that the assembled Russian force on the frontier is growing at a rate that would give Putin the force he needs for a full-scale invasion -- some 150,000 soldiers -- by mid-February.

They said Putin wants all possible options at his disposal: from a limited campaign in the pro-Russian Donbas region of Ukraine to a full-scale invasion.

Russia denies that it is planning to invade Ukraine.

If Moscow does opt for a full-scale attack, the invading force could take the capital Kyiv and topple President Volodymyr Zelensky in a matter of 48 hours, the officials said.

They estimated such an attack would leave 25,000 to 50,000 civilians dead, along with 5,000 to 25,000 Ukrainian soldiers and 3,000 to 10,000 Russian ones.

It could also trigger a refugee flood of one to five million people, mainly into Poland, the officials added.

- Special forces -
President Joe Biden has decided to send American forces to Poland to protect NATO members, as diplomats work furiously to try to persuade Russia to pull its troops back from the border with Ukraine.

The first contingent of US soldiers arrived Saturday.

Russia has also announced what it calls joint military maneuvers with Belarus, where it has sent several battalions to the north of Kyiv and in the Brest region, not far from the border with Poland.

US intelligence has concluded that Russia is continuing to muster a major military force on its border with Ukraine.

Two weeks ago, a total of 60 Russian army battalions were positioned to the north, east and south of Ukraine, particularly in the Crimean peninsula, which Russia annexed after an invasion in 2014.

But on Friday, there were 80 battalions and 14 more were en route from elsewhere in Russia, US officials said.

They added that some 1,500 Russian special forces soldiers known as Spetsnaz arrived along the Ukraine border a week ago.

- Naval forces assembling -
A major Russian naval force is also positioned in the Black Sea, equipped with five amphibious vessels that could be used to land troops on Ukraine's southern coast, the US officials said.

They added that another six amphibious craft were observed leaving the Barents Sea north of Russia, sailing past Britain and through the Strait of Gibraltar, apparently on their way to the Black Sea.

In other deployments, Russia has positioned fighter planes near Ukraine, as well as bombers, missile batteries and anti-aircraft batteries, US officials said.

On Thursday, the United States said it had evidence that Russia was preparing a video depicting a bogus attack by Ukraine that would serve as a pretext for a real Russian assault on Ukraine.