Biden continues threats of economic sanctions over Ukraine, while Putin appears undeterred

American President Joe Biden continues to threaten economic sanctions and trade restrictions on Russia if it further invades Ukraine, while Russian President Vladimir Putin appears undeterred by the warnings.

The United States currently maintains sanctions on Russia in response to the 2014 capture of Ukraine's Crimean peninsula, human rights abuses, and malicious cyber activities and influence operations, among other things.

Russia maintains large numbers of troops along the Ukrainian border, raising international fears that it will invade. 

An administration official told reporters on Monday that the U.S. is "prepared to implement sanctions with massive consequences that were not considered in 2014."

"The deepening selloff in Russian markets, its borrowing costs, the value of its currency, market-implied default risk reflect the severity of the economic consequences we can and will impose on the Russian economy in the event of a further invasion," the senior official said.

Biden has not dismissed sanctioning Putin personally if he invades Ukraine.

The administration argues that Russia felt "pain" from the 2014 sanctions, which were issued when Biden was vice president.

The Biden administration plans on implementing export controls as well that would prohibit the export of sophisticated technology from the U.S. to Russia. 

Pentagon press secretary John Kirby told reporters Tuesday that Biden "has made clear in two conversations with Mr. Putin that there will be severe consequences largely of an economic nature if he conducts another invasion, another incursion of Ukraine."

Biden said he has "made it clear to President Putin" that if Russia continues building up troops along the Ukrainian border, the United States would "beef up" NATO's presence in Eastern Europe.

"We have no intention of putting American forces or NATO forces in Ukraine," Biden said, reiterating that "there are going to be serious economic consequences if he moves."

Predicting if Putin will invade is "a little bit like reading tea leaves," but it all comes down to his decision, Biden told reporters. 

Russia has reportedly begun military exercises near Ukraine with thousands of troops and dozens of fighter jets. Around 100,000 Russian troops are currently estimated to be near the Ukranian border. The Kremlin has accused the United States of escalating tensions in the area by placing 8,500 servicemembers on heightened alert to deploy to Eastern Europe.