Civilian flights within Ukraine were restricted through the end of Thursday, according to a notice to airmen.
The flights were restricted “due to potential hazard for civil aviation,” said the notice, posted on an Federal Aviation Administration website. Russia was poised to launch an attack, officials said Wednesday night.
The notice came just before Russian President Vladimir Putin announced that his forces would launch a military operation in Ukraine.
Several foreign airlines, including Lufthansa and KLM have suspended Ukraine flights due to worries about a potential invasion of Ukraine by Russia.
LOT Polish Airlines Flight 755 headed for Kyiv returned to Warsaw around the time the order was issued.
Earlier Russia restricted flights along the country’s eastern border with Ukraine. U.S. aviation authorities first prohibited U.S. aircraft from flying over eastern Ukraine since Malaysia Airlines Flight 17 was shot down in the region.
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