(WASHINGTON) — The State Department has escalated its warning to U.S. citizens in Belarus, where thousands of Russian troops have massed for menacing military exercises — now urging them to leave the country “immediately.”

The stark new warning comes as U.S. officials fear a possible Russian attack on neighboring Ukraine could unfold in the coming days, prompting the State Department to shutter its embassy facility in the capital Kyiv and relocate them to the western city Lviv.

Belarus and Russia launched military exercises Thursday, bringing thousands of Russian troops and advanced weaponry and equipment to the landlocked country that borders both Russia and Ukraine. Its strongman leader, Belarus President Alexander Lukashenko, has drawn increasingly closer to Russian President Vladimir Putin after cracking down on political opposition, fomenting a migrant crisis in Europe and facing tough Western sanctions.

The State Department had already urged American citizens “do not travel to Belarus” because of that domestic crackdown and the risk of “arbitrary enforcement of laws” and detention, as well as COVID-19.

But in a new advisory Monday evening, it added a warning about the “unusual and concerning Russian military buildup along Belarus’ border with Ukraine” and added, “U.S. citizens in Belarus should depart immediately via commercial or private means.”

The “situation is unpredictable, and there is heightened tension in the region,” the advisory states, mirroring the increasingly urgent tone from the U.S. embassy in Ukraine, which urged Americans on Saturday to “depart immediately” as well.

The warning also noted, “The U.S. government’s ability to provide routine or emergency services to U.S. citizens in Belarus is already severely limited due to Belarusian government limitations on U.S. Embassy staffing.”

The embassy in Minsk, the capital of Belarus, had previously ordered the departure of family members on Jan. 31, with a very small group of U.S. diplomats still in the country.

In addition, the State Department is urging Americans to “depart immediately” from Transnistria, which is part of Moldova — the landlocked country on Ukraine’s southwestern border.

The urgent warning doesn’t apply to the entire country, but just to Transnistria, an unrecognized breakaway region where Russia has stationed troops against the Moldovan government’s will as “peacekeepers,” similar to Russian troops in two disputed regions of Georgia, the small former Soviet republic.

Like Belarus, Moldova had been on the State Department’s Level 4: “Do Not Travel” list because of COVID-19, but now in its new advisory, it warns of the “unusual and concerning Russian military activity around Ukraine, and the unresolved conflict between the breakaway region of Transnistria and the central government; U.S. citizens in Transnistria should depart immediately.”

U.S. officials, including Secretary of State Antony Blinken, have repeatedly referenced Transnistria during the current crisis as another example of Russia’s aggression in the region in recent years, along with Georgia and Ukraine.

Ukrainian officials went even further last month. Its defense intelligence agency said it had evidence that Russia was planning a false flag provocation against its own soldiers in Transnistria to justify an invasion of Ukraine — an accusation the Russian government denied.

The Biden administration has said it will not use the U.S. military to help evacuate American citizens if war breaks out in the region — with the memory of Afghanistan hanging over them. That historic, chaotic operation ultimately evacuated some 124,000 people, but the State Department has made clear it was not a precedent.

Instead, the U.S. has used increasingly dire warnings to private Americans in Ukraine, and now Belarus and Transnistria, to leave now while commercial flight options or land border crossings are available.

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