The Trump administration on Tuesday banned carrying electronic devices larger than cell-phones on to planes coming to the US from 10 airports in Muslim-majority countries in the Middle East and North Africa.
The restriction imposed in response to unspecified terrorism threats comes weeks after President Donald Trump's second travel ban was partly blocked by a federal court in Hawaii.
The airports are in Cairo, Istanbul, Kuwait City, Doha, Casablanca, Amman, Riyadh, Jeddah, Dubai and Abu Dhabi.
The Department of Homeland Security said passengers travelling from those airports could not bring devices, such as tablets, portable DVD players, laptops and cameras, into the main cabin. Instead, they must be in checked baggage.
The rules do apply to US citizens travelling on those flights, but not to crew members on foreign carriers.
Homeland Security will allow passengers to use larger approved medical devices.
TRT World's Oliver Whitfield-Miocic explains.
About 50 flights will be affected per day
The airports affected by the electronics rules are served by nine airlines that fly about 50 direct flights a day from those cities to the US, senior government officials said.
The carriers are: Royal Jordanian Airlines, Egypt Air, Turkish Airlines, Saudi Arabian Airlines, Kuwait Airways, Royal Air Maroc, Qatar Airways, Emirates and Etihad Airways.
These airlines have until Friday to comply with the new policy, which took effect early on Tuesday and will be in place indefinitely.
Several of the carriers, including Turkish Airlines, Etihad Airways and Qatar Airways, said early on Tuesday that they were quickly moving to comply.
Royal Jordanian and Saudi Airlines said on Monday that they were immediately putting the directive into place.
TRT World spoke to Kevin McAleese who brings more from Washington DC.
The new restrictions were prompted by reports that militant groups want to smuggle explosive devices in electronic gadgets, officials told reporters on a conference call on Monday.
They did not provide further details on the threat.
Officials said the decision had nothing to do with President Donald Trump's efforts to impose a travel ban on six majority-Muslim nations.
DHS spokeswoman Gillian Christensen said the government "did not target specific nations. We relied upon evaluated intelligence to determine which airports were affected."
On March 6, Trump signed a revised executive order barring citizens from Iran, Libya, Syria, Somalia, Sudan and Yemen from travelling to the United States for 90 days.
Two federal judges have halted parts of the ban, saying it discriminates against Muslims. Trump has vowed to appeal up to the Supreme Court if necessary.