Russian soldiers have moved into two separatist-controlled regions in eastern Ukraine under orders from Russian President Vladimir Putin. Troops and military hardware reportedly arrived at the two regions, recognized by Russia as independent states.

The arrival of the troops has increased fears in the West of what could become a full-scale war. Local media reports said tanks and other military vehicles arrived at the separatist-controlled city of Donetsk after Russia formally acknowledged them as breakaway regions. Russian officials said the troops were deployed to the regions to "keep the peace."

Witnesses said around five tanks had been posted around the edge of the city and two more patrolling city streets. The tanks reportedly had no markings indicating they were Russian.

The U.S. and some European countries have warned that the move may be a precursor to a full-scale offensive in Ukraine. Linda Thomas-Greenfield, U.S. ambassador to the United Nations, said Russia's acknowledgment of breakaway regions could be part of its invasion strategy.

In a televised address, Putin aired out his grievances against western interference. He argued that eastern Ukraine belonged to Russia as it is "ancient Russian land." Putin signed a decree recognizing the self-proclaimed Donetsk People's Republic and the Lugansk People's Republic as independent states.

As a precaution, U.S. diplomatic staff from the nation's embassy in Kyiv has been told to postpone their move to the city of Lviv and stay in Poland instead. U.S. officials said that the deployment of troops to the breakaway states might not constitute a full invasion, but it might still lead to serious economic sanctions against Russia, given that it now has troops within Ukraine.

U.S. President Joe Biden, who had recently concluded a meeting with German Chancellor Olaf Scholz and French President Emmanuel Macron, has signed an executive order to halt all business activities, including the import and export of goods, within the two breakaway regions.

U.S. Secretary of State Antony Blinken said the executive order is meant to prevent Russia from profiting from its actions, which are in violation of international law. The order is separate from the planned sanctions intended to be imposed against Russia if it launches a full-scale invasion.

In a speech to the country early Tuesday, Ukrainian President Volodymyr Zelenskiy, who got a support call from Biden, accused Russia of sabotaging peace talks and ruled out territorial compromises. Scholz's spokeswoman stated that Germany, France, and the U.S. had decided to retaliate with sanctions, while British Foreign Minister Liz Truss indicated that the nation is also prepared to impose sanctions.