The State Department issued a Do Not Travel advisory to Ukraine on Sunday night, “due to the increased threats of Russian military action and COVID-19.”

Over the last year, Russian President Vladimir Putin has been moving tens of thousands of troops to the border with Ukraine, and the United States has warned that an invasion could be imminent. In the travel advisory, the State Department said the “security conditions, particularly along Ukraine’s borders, in Russia-occupied Crimea, and in Russia-controlled eastern Ukraine, are unpredictable and can deteriorate with little notice.” 

The State Department also announced on Sunday night that “out of an abundance of caution,” it is reducing staff levels at the U.S. Embassy in Kyiv, one day after families of embassy personnel were ordered to evacuate the city. Additionally, the State Department is asking U.S. citizens in Ukraine to “consider departing now using commercial or other privately available transportation options,” reminding them that any military action by Russia would “severely impact” the embassy’s ability to provide consular services.

Essential personnel will stay at the embassy, a State Department official told reporters on Sunday night, and it will continue operating “uninterrupted.”