The first 100 U.S. troops reinforcing NATO allies on the eastern flank have arrived in Romania amid rising tensions on the Russia-Ukraine border, Defense Minister Vasile Dancu said on Tuesday.

"The Americans have arrived," he said. "Over 100 specialist U.S. soldiers together with our logistics specialists are preparing, which means it will not be long before the rest of the troops arrive."

Last week, the Pentagon started to send more than 3,000 troops to Romania and Poland to reassure its NATO allies, while Germany announced it was considering a boost to its existing military deployment in Lithuania.

The Pentagon said it will relocate a Stryker squadron of around 1,000 U.S. service members from Vilseck, Germany, to Romania. In Poland, troops began arriving on Saturday.

As part of a future NATO mission, France also plans to send troops to Romania and has offered to be the lead nation of a future NATO mission, which could see about 1,000 troops from various countries.

Read more:

NATO considers to reinforce allies if Russian troops stay in Belarus

No intention of putting U.S. or NATO troops in Ukraine: Biden

(With input from agencies)