Biden deploying thousands of troops to Eastern Europe amid tensions with Russia over Ukraine

• The US is officially sending troops to Eastern Europe amid tensions with Russia over Ukraine, CNN reported.
• The troops are not being deployed to Ukraine, which is not a NATO member.
• Putin has railed against NATO expansion in the region.

President Joe Biden has officially approved new military deployments to Eastern Europe amid concerns that a Russian invasion of Ukraine could be imminent, CNN reported on Wednesday, citing US officials. 

The deployment will occur in the "coming days," the report said, which came after the US placed 8,500 troops on high alert over the tensions.

Roughly 2,000 troops will be sent to Poland, CNN said, among deployments to other countries in the region. Additionally, about 1,000 troops will be sent to Romania, per the Wall Street Journal.

Biden on Friday announced that the US would be "moving troops to Eastern Europe in the NATO countries in the near term."

"Not too many," the president added. 

The US troop deployments to Eastern Europe are meant to serve as a deterrent against further Russian aggression, and a signal to Putin that Washington has NATO's back. Biden has signaled that US troops won't move to defend Ukraine if Russian forces attack, but has threatened harsh sanctions intended to batter the Russian economy and target top officials.

Given that Ukraine is not a NATO member, the Biden administration has ruled out deploying troops to defend it against Russia in the event of an invasion. NATO operates under the principle of collective defense, considering an attack on one member an attack on all. Ukraine has sought to join NATO for years, and maintains a strong partnership with the Western military alliance. The US has also provided Ukraine will billions in security assistance, including roughly $650 million in the past year. Other NATO members have provided similar support to Kyiv, including lethal aid.

Kyiv's NATO ambitions, and the alliance's presence in Eastern Europe more generally, are at the heart of the tensions between Moscow and the West. Russian President Vladimir Putin has accused the alliance of not respecting his red lines in the region, blaming NATO for the crisis despite his history of aggression toward Ukraine. 

Russia invaded Ukraine in 2014, annexing Crimea in the process. Russia has also supported rebels in a war against Ukraine since 2014 that's killed over 13,000 people.

At the moment, Russia has roughly 100,000 troops gathered on Ukraine's border. Moscow says it has no plans to invade, but the Biden administration has warned a Russian military incursion could be imminent. 

Amid diplomatic efforts to stave off a broader confrontation, the Kremlin has demanded that Ukraine and Georgia be barred from ever joining NATO. The US and the alliance, which recently delivered written responses to Moscow's demands, have remained firm that the alliance's open door policy is not up for discussion. 

Putin on Tuesday accused the West of ignoring Russia's primary security concerns, but seemingly left the door open for continued diplomatic talks. "I hope that we will eventually find a solution, although we realize that it's not going to be easy," Putin said, according to The Associated Press.