The Trump administration is considering banning laptops from the passenger cabins of all international flights to and from the US, homeland security secretary John Kelly said on Sunday.

Kelly, a retired general, was asked on Fox News Sunday if he would expand an existing ban to cover laptops on all international flights into and out of the US.

“I might,” he said.

Such a move would dramatically expand the ban, announced in March, that affects about 50 flights per day from 10 cities, mostly in the Middle East.

The ban prevents travelers from bringing laptops, tablets and certain other devices on board in carry-on bags. All electronics bigger than a smartphone must be checked in.

The measure applies to nonstop US-bound flights from 10 international airports in 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 airlines, are affected.

Earlier this month, reports said the Trump administration would broaden the ban to include planes from the European Union, affecting trans-Atlantic routes that carry as many as 65 million people a year.

US officials have said that initial ban was not based on any specific threat but on longstanding concerns about extremists targeting jetliners. Speaking on Fox and Friends on Friday, Kelly said some people would “never leave the house” if they knew what he knew about terrorist activity.

“There’s a real threat,” Kelly said on Sunday, adding that terrorists are “obsessed” with the idea of downing a plane in flight, “particularly if it’s a US carrier, particularly if it’s full of mostly US folks. It’s real.”

Kelly said that the US would “raise the bar for, generally speaking, aviation security much higher than it is now, and there’s new technologies down the road, not too far down the road, that we’ll rely on”.

“It is a real sophisticated threat,” he said, “and I’ll reserve making that decision until we see where it’s going.”

In an interview with ABC’s This Week, Kelly commended what he called “unbelievable cooperation of the Europeans, the Middle Easterners, the Asians” in assessing the situation.

“You just have to be vigilant,” he said. “You know, it’s trite but people should understand if they see something they should say something. Since I’ve been in this job… I have called my counterpart in the United Kingdom three times to offer my condolences for terrorist attacks.

“Three times, in 120 days. This is nonstop. They are out there trying to hurt us every day. The good news is for our country that we have not suffered anything like this from external threats since 9/11.

“That goes to the effectiveness of our military overseas, CIA, our NSA, and at home DHS, local law enforcement, FBI. But it’s relentless, it’s nonstop. They’re trying to hurt us every day. We just have to be vigilant.”