Airline passengers should not turn on or charge their Samsung Electronics' Galaxy Note 7 smartphones during flights or stow them in checked baggage due to concerns over the phone's fire-prone batteries, the U.S. Federal Aviation Administration said.
In a statement on Thursday, the FAA said it "strongly advises" passengers to follow its guidance "in light of recent incidents and concerns raised by Samsung about its Galaxy Note 7 devices."
The South Korean manufacturer announced last week it was recalling all Galaxy Note 7 smartphones equipped with batteries it has found to be prone to catch fire.
Delta Air Lines, the No.2 U.S. airline by passenger traffic, said it is still studying the issue.
"Delta is in constant contact with the FAA and other bodies in its run of business as a global airline. We will comply with any directive and are studying this matter. Safety and security is always Delta's top priority," spokesman Morgan Durrant said in a statement,
Vaughn Jennings, a spokesman for Washington-based trade group Airlines for America, said the organization was "closely monitoring any developments as this issue evolves."