Commercial airlines that normally cross eastern Ukraine on their flights to Europe, Asia and elsewhere are detouring away from the volatile region in light of Thursday's suspicious crash of Malaysia Airlines Flight 17.
The Federal Aviation Administration said in a statement Thursday that the agency had been in contact with U.S. airlines after the crash.
"The agency confirms that carriers have voluntarily agreed not to operate in the airspace near the Russian-Ukraine border. The FAA is monitoring the situation to determine whether further guidance is necessary," the statement said.
Ukrainian officials say that the plane might have been shot down.
Tensions have been high between Ukraine and Russia since street protests forced former pro-Moscow President Viktor Yanukovych from power in February. Russia subsequently annexed Ukraine's southeastern Crimea region, and a pro-Russian separatist rebellion has been raging in Ukraine's eastern Luhansk and Donetsk regions.
In April, U.S. airlines were prohibited by the FAA from flying in air space surrounding Crimea, but Thursday's crash site was not within the restricted area.
The plane went down near the town of Torez in the Donetsk region of eastern Ukraine.
The European Aviation Safety Agency also warned in April against flying in the same area, called the Simferopol Flight Information Region.
In light of the crash, airlines around the world are rerouting flights.
"We're taking a wide detour around eastern Ukraine," said Lufthansa spokesman Nils Haupt. That detour will be in effect at least through Friday, he said. Lufthansa had four scheduled flights Thursday that would normally cross over eastern Ukraine.
"We are closely watching the situation" to decide flight plans beyond the next couple days, he said. "It's a precautionary measure to protect the safety of our passengers."
Lufthansa said it isn't making any changes to its two daily flights going from Frankfurt to Kiev or its one daily flight from Munich to Odessa, because they don't cross over that airspace.
With only once-a-day service between Heathrow and Kiev, British Airways doesn't have any flights in the area of the crash site, according to a spokesperson. "We are keeping those (Kiev) services under review, but Kiev is several hundred kilometers from the incident site."
A Kiev-bound Emirates flight turned around on Thursday and returned to Dubai "due to the safety concerns raised with the latest reports on Malaysian flight MH17," and suspended all flights to Kiev immediately until further notice, according to a company statement.
Other Emirates flights to and from the United States and Europe fly a route outside the area where the crash occurred, the company said.
American carriers including Delta Air Lines are also avoiding the region.
"Out of an abundance of caution, Delta is not routing flights through Ukrainian airspace and is monitoring the situation involving Malaysia Airlines Flight 17," the airline said in a statement.