FILE - This is a  July 29, 2002  file photo of  a laptop is used on a plane . Britain's government  Tuesday March 21, 2017 banned electronic devices in the carry-on bags of passengers traveling to the U.K. from six countries, following closely on a similar ban imposed by the United States. (Chris Ison/PA, File via AP)
FILE - This is a July 29, 2002 file photo of a laptop is used on a plane . Britain's government Tuesday March 21, 2017 banned electronic devices in the carry-on bags of passengers traveling to the U.K. from six countries, following closely on a similar ban imposed by the United States. (Chris Ison/PA, File via AP) Credit: Chris Ison

Washington — U.S. and British officials said Tuesday the decision to bar laptops and tablets from the cabins of some international flights wasn’t based on any specific threat but on longstanding concerns about terrorists targeting jetliners.

Unimpressed, some travelers and civil liberties groups denounced the ban, raising concerns that included lost worktime on long flights and worries that checking laptops in baggage will make them more vulnerable to theft.

Under the new bans, electronic devices larger than smartphones, such as laptops, tablets and gaming devices, will have to be checked on some international flights. American officials announced the U.S. ban early Tuesday, and the British followed later in the day after discussions between the countries.

The U.S. ban affects flights from Amman, Jordan; Kuwait City, Kuwait; Cairo; Istanbul; Jeddah and Riyadh, Saudi Arabia; Casablanca, Morocco; Doha, Qatar, and Dubai and Abu Dhabi in the United Arab Emirates. About 50 flights a day, all on foreign carriers, will be affected. Senior Trump administration officials who briefed reporters about the ban said no U.S.-based airlines have nonstop flights from those cities to the U.S.

The British security rules will apply to flights from Turkey, Lebanon, Jordan, Egypt, Tunisia and Saudi Arabia.

A U.S. government official said the ban was not prompted by any new or specific threat uncovered in recent days, but rather was based on awareness of continuing terrorist desires to target commercial aircraft. Terrorists are aggressively pursuing new methods to conduct attacks, including smuggling explosives in consumer items, the official said.

That official spoke on the condition of anonymity because the official was not authorized to discuss internal government security discussions.

The administration officials who spoke to reporters earlier said the security change was the result of “evaluated intelligence.” They noted that an explosion aboard a Daallo Airlines flight in Somalia last year was believed to have been the result of a laptop-borne bomb. That explosion killed only the suspected bomber.

A British security official also said there have not been, to that official’s knowledge, recent European-directed plots involving such explosive devices. The official spoke on the condition of anonymity because the official was not authorized to speak publicly about ongoing intelligence operations.

Bennet Waters, principal at the Chertoff Group, a Washington consulting firm, and a former senior official at the Homeland Security Department, said on Tuesday that threats to commercial aircraft have been evolving since before the Sept. 11, 2001, terrorist attacks.

He said when he was in the government, the threat to aircraft was “very clear, very consistent and it was very persistent.”

The new U.S. and British rules for electronics appear to address an evolving threat. The targeted airports are in a region where the terror threat has been elevated for several years.

The 10 airports singled out by the U.S. may have been selected because screening equipment and procedures for carry-on luggage may not be effective enough to detect certain types of non-metallic explosive devices. Waters said screening of checked bags is often more intensive.

Travelers expressed concerns that the new requirements would curb their efforts to work on long flights and subject their costly electronics to damage or theft.

Banu Akdenizli, an associate professor of communications at the Doha, Qatar, campus of Northwestern University, said she is scheduled to fly to the U.S. in early April for a conference, where she will be a speaker and moderator, in Greensboro, N.C. The Turkish native said traveling 17 hours without her laptop will cost her precious time to work and prepare for the conference. She said she’s also worried her computer could be stolen.

“There are massive amounts of data on my computer,” Akdenizli said.

The U.S. rules took effect on Tuesday, though airlines will have until 3 a.m. on Saturday to implement them or face being barred from flying to the United States, the Trump administration officials said.