(Bloomberg) -- Users of Samsung Electronics Co.’s troubled Note 7 smartphonewere urged to immediately turn off and stop charging them by a U.S.safety agency as aviation authorities around the world orderedpassengers not to use them during flights.

The U.S. Consumer Product SafetyCommission said Friday it is in talks with Samsung on anofficial recall of the devices as soon as possible, the agency saidin a release. About three dozen of the devices, released just threeweeks ago, had batteries that caught fire or exploded.

“This consumer warning is based on recent reports involvinglithium-ion batteries in certain Note 7 devices that have resultedin fires,” the CPSC said in its release. “These incidents haveoccurred while charging and during normal use, which has led us tocall for consumers to power down their Note 7s.”

The troubles come at a difficult time for Samsung. The companyrolled out the Note 7 last month to give it a head start on AppleInc.’s new iPhone, which was unveiled this week. But that advantagehas now disappeared. Samsung shares fell 3.9 percent in tradingFriday in Korea, the biggest drop since Jan. 4.

Voluntary recall

The recent introduction of new products by the two leaders of theglobal smartphone market are critical to their competition,Bloomberg Intelligence analyst John Butler said in aninterview.

“Samsung’s troubles, and they’re meaningful at this point, are apositive development for Apple and its competitive positionvis-a-vis Samsung," Butler said.

"We’re rolling quickly into the holiday quarter, so Samsung hasto move quickly to recall the Note 7 devices with faulty batteriesand get replacement units to people who already bought this model,”he said.

The Suwon, South Korea-based company has already announced avoluntary, worldwide recall of the all 2.5 million of thesmartphones it has already shipped, at a cost to the companyestimated at as much as $1 billion.

(Source: YouTube)

Aviation concerns

The CPSC action came as aviation regulators in several countriesand airlines advised passengers against turning on or charging thedevices during flights.

The European AviationSafety Agency on Friday issued such a warning andcautioned against packing them in checked bags, according to aposting on its website. That followed a non-binding warning issuedThursday by the U.S. Federal AviationAdministration.

“In light of recent incidents and concerns raised by Samsungabout its Galaxy Note 7 devices, the Federal AviationAdministration strongly advises passengers not to turn on or chargethese devices on board aircraft and not to stow them in any checkedbaggage,” the agency said late Thursday.

India, Singapore

India’s Directorate General of Civil Aviation banned switchingon the phones during flights, or placing them in checked bags thataren’t carried in the cabin. Singapore Airlines Ltd. has barredtravelers from powering up or charging the devices on flights, thecompany said in an e-mail.

Samsung issued a press release Friday saying “ consumer safetyand peace of mind are our top priority.”

Following the FAA’s statement, U.S. carriers were taking avariety of steps. Delta Air Lines Inc. posted a notice on itswebsite telling passengers to comply with the FAA’sguidance.

Southwest Airlines Co. will share information on its website andsocial-media channels to make passengers aware of the FAArecommendations, said Lisa Tiller, a spokeswoman for theDallas-based carrier. Spirit Airlines Inc. said all passengers willreceive a copy of the FAA notice 12 hours prior to flying.

American Airlines Group Inc. and JetBlue Airways Corp. said theyare consulting with the FAA on the issue. JetBlue added that it istrying to get more FAA guidance for its employees so they cananswer customer questions.

The Airlines for America tradegroup, which represents most large U.S. carriers, said in anemail it is closely monitoring the situation.

Lithium batteries

The actions are the latest to focus on the risks of lithium-basedbatteries on aircraft, which have been linked to three accidents oncargo carriers, two of which were fatal. The FAA has logged dozensof more minor incidents in which the batteries caught fire,smoldered or exploded on airline flights.

The United Nations’ International Civil Aviation Organization inFebruary voted to ban passenger airlines from carrying bulkshipments of rechargeable lithium-ion batteries, such as those onthe Samsung device. The group stopped short of placing restrictionson batteries contained in devices because any fires that occur aremuch easier to extinguish.

Related: Warning issued on exploding bulk-battery shipmentson planes

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