Homeland Security Department stepped up security of US-bound flights, requiring tougher screening of mobile phones and other electronic devices to the United States.

US authorities are planning to ban passengers traveling on certain US-bound foreign airline flights from carrying into the cabin larger electronic devices in response to an unspecified terrorist threat, US officials told Reuters on Monday.

The new rule is expected to be announced as early as Monday by the Department of Homeland Security, the officials said, adding that it had been under consideration since the US government learned of a threat several weeks ago.

A source said the rule would cover nearly a dozen foreign airlines. A separate government official confirmed an Associated Press report that the ban will impact 10 airports in eight countries in the Middle East and North Africa. Reuters reported earlier the ban would include airlines based in Jordan and Saudi Arabia. The officials did not name the other countries.

The officials said no American carriers were affected by the ban, which would apply to devices larger than a cell phone, and none travel directly to the airports impacted from US cities Passengers would be allowed to carry larger devices in their checked luggage like tablets, portable DVD players, laptops, and cameras.

Royal Jordanian Airlines said in a tweet on Monday that US-bound passengers would be barred from carrying most electronic devices aboard aircraft starting Tuesday at the request of US officials, including those that transit through Canada. Passengers can still carry cell phones and approved medical devices.

Al Riyadh newspaper, which is close to the Saudi government, reported that the civil aviation authority had informed “airlines flying from the kingdom’s (Saudi) airports to US airports of the latest measures from US security agencies in which passengers must store laptops and tablets” in checked in baggage.

Al Riyadh quoted a civil aviation authority source as saying that these measures from senior US authorities were related to the Saudi interior ministry. Saudi Airlines confirmed in a tweet that US transportation authorities had barred carrying larger electronic devices in cabin luggage. The White House declined to comment.

A spokesman for the US Department of Homeland Security, David Lapan, said the agency has “no comment on potential security precautions, but will provide an update when appropriate. Homeland Security Secretary John Kelly called congressional lawmakers this weekend to notify them of the plan, congressional aides said

In July 2014, the Homeland Security Department stepped up the security of US-bound flights, requiring tougher screening of mobile phones and other electronic devices and requiring them to be powered up before passengers could board flights to the United States.

UK follows electronics ban, bans six countries

Passengers flying directly to Britain from Egypt, Jordan, Lebanon, Saudi Arabia, Tunisia and Turkey will be banned from taking laptops and tablet computers into the plane cabin, the government announced Tuesday.

“Our top priority will always be to maintain the safety of British nationals,” a spokesman said after the US imposed a similar ban, warning that extremists plan to target planes with bombs in electronic devices.

Emirates, Etihad ‘not advised of new restrictions’

Meanwhile, Emirates Airline and Etihad Airways have said they have not been advised of any new restrictions on carrying electronic devices on US flights, the Middle East airlines said on Tuesday.

A source said the rule would cover around eight to 10 foreign airlines. A separate government official confirmed an Associated Press report that the ban will affect 10 airports in eight countries in the Middle East and North Africa.

“At this time we have not received any notification of changes to cabin luggage restrictions on US flights,” an Emirates spokeswoman told Reuters in an emailed statement. An Etihad spokesman also said the Abu Dhabi airline had not received new guidance.

In July 2014, the Homeland Security Department stepped up the security of US-bound flights, requiring tougher screening of mobile phones and other electronic devices and requiring them to be powered up before passengers could board flights to the United States.

No instructions, says EgyptAir

Egyptian officials at the Cairo International Airport say they have not received any instructions on banning passengers from bringing laptops, iPads, cameras and some other electronics on board direct flights to the United States.

The officials say that a New York-bound EgyptAir flight departed on Tuesday and that passengers were allowed to take their laptops and other electronics on board in their carry-on luggage. Egypt’s Foreign Minister Sameh Shoukri was among the passengers on board the New York flight.