Iran has issued a NOTAM (Notice to Airmen) late on Wednesday night, closing its airspace to all flights, as Western military officials say US military action in the country is "imminent."
Flight tracker websites showed the airspace over Iran and Iraq emptying rapidly prior to the NOTAM's issuing. The advisory is valid for a little more than two hours, Flightradar24 said.
"All the signals are that a US attack is imminent, but that is also how this administration behaves to keep everyone on their toes. Unpredictability is part of the strategy," a Western military official told Reuters later on Wednesday.
Shortly before the NOTAM was issued, US President Trump held a press conference in which he said he was told that the killings in Iran had stopped.
When asked if the US was still considering military action, Trump answered, "We're going to watch and see what the process is."
Foreign nations encourage their citizens to leave Iran
Both Poland and Italy have urged their citizens to leave Iran immediately. The British embassy in Tehran has been temporarily closed. Less than 24 hours before, the US had urged its own citizens to leave.
The US has also withdrawn military personnel from the US military's Al Udeid Air Base in Qatar.
Earlier on Wednesday, a senior Iranian official told Reuters that Iran warned regional countries that it would strike US military bases in those countries in case of a US attack.
This is a developing story.