KUSA - Russia is deploying thousands of troops in its regions near the Ukrainian border and there are concerns the move is precursor to an invasion either of Ukraine or other neighboring countries.

"There are some worries about what Russia is going to do in the near future," said Christoph Stefes, Associate Professor of Political Science at CU Denver. "There are fears it might actually invade eastern parts of Moldova it might actually try to take over parts of eastern Ukraine."

The concern comes just days after Russia formally annexed Crimea in a controversial move that many other nations are refusing to recognize.

"By international law it [Crimea] wouldn't be [part of Russia] because nobody else but Russia has accepted this status yet," said Stefes.

Still Russia is moving forward with its takeover of the region.

"Crimea is now part of Russia, I think tomorrow [Monday] they will introduce the ruble, the Russian currency, so by all accounts it's part of Russia," said Stefes.

It's a complicated situation for even Stefes to explain.

"Ukraine does not accept Crimea to be part of Russia so I don't know how this plays out."

There is growing concern about the large number of troops amassed along Russia's eastern border with Ukraine. Russia's deputy defense minister says the number of troops in the area does not exceed international treaty limits. Other officials worry Russia could be preparing for an invasion.

"One of the NATO generals said today [Sunday] that there are a lot of Russian right now at the border, they are very readied to move very fast into eastern Moldova. That is a possibility," said Stefes. "Is it just a threat, or is it real plans, I don't know. If they really moved into Ukraine, in territory, and into Moldova, that would be a huge problem."

Professor Stefes says any type of invasion would likely force further action by the United States and members of the European Union. So far, they've imposed some economic sanctions on Russia, but they haven't appeared to have much impact. Stefes says the next few days will be critical as we learn more about Russia's true intentions.

"I think the next week is going to be very decisive, if the next week stays calm the OCE does its mission, the Russians stay out of it, maybe even withdraw some of its troops, I think we are over the worst," Stefes said. "But it could also happen that we are getting into a hot war, like a shooting situation."