Washington, Jan 25 (IANS): The US Department of Defense has announced that nearly 8,500 US troops have been put on heightened alert for a possible deployment due to escalating tensions on the Russia-Ukraine border, but there is no decision on formal deployments.

John Kirby, the Defense Department's spokesperson, said on Monday during a press briefing that putting US forces on heightened alert is to ensure that the US will get ready to respond to a possible decision by the North Atlantic Treaty Organisation (NATO) to deploy its 40,000-strong multinational response force known as NRF, which could be shored up on short notice.

"This is really about reassuring the eastern flank of NATO," Kirby said, adding the order, which came from Defense Secretary Lloyd Austin at the direction of President Joe Biden, was about "proving how seriously the US takes our commitment to NATO" and to the alliance's collective defense commitment, Xinhua news agency reported.

"All told, the number of forces that the Secretary has placed on heightened alert comes up to about 8,500 personnel," the spokesperson said.

Kirby stressed that no decision has been made on deploying US forces, and that the troops on high alert include "additional brigade combat teams, logistics personnel, medical support, aviation support, intelligence, surveillance and reconnaissance."

The spokesperson also reiterated Biden's position that the US will not be sending its troops into Ukraine in the event that war breaks out between Kiev and Moscow, but that the West is still determined to deter the Kremlin from launching an invasion through the threat of sanctions and military aid to Ukraine.

The Pentagon's prepare-to-deploy order came one day after the State Department authorised the voluntary departure of US government employees at the US Embassy in Kiev and required their family members to leave Ukraine.