(Claritza Jimenez/The Washington Post)

U.S. officials on Wednesday announced enhanced security and screening measures for all commercial flights to the United States but backed away from a proposal to expand a ban on laptops and other electronic devices — unless airlines and airports refuse to comply with the new rules.

Since March, passengers on flights to the United States from certain primarily Muslim-majority countries have been prohibited from bringing electronic devices larger than a cellphone on board with them. But those restrictions could be lifted if the affected airlines and airports adopt the new security protocols, officials said.

Department of Homeland Security officials said airlines and airports will be responsible for implementing the changes and communicating new procedures to the traveling public. Officials declined to offer specifics about the changes, citing security concerns, but said they could include enhanced screening of laptops and smartphones and increased security protocols around aircraft and in passenger areas.

The hope is that the new requirements will not result in longer wait times at security checkpoints or be prohibitively costly for airlines and airports to implement.

In a briefing with reporters, senior DHS officials said the requirements will “raise the baseline” on aviation security worldwide. The directives are focused on preventing terrorists from circumventing aviation security.

“It is time that we raise the global baseline of aviation security,” Homeland Security Secretary John F. Kelly said. “We cannot play international whack-a-mole with each new threat.”

Despite talk of expanding a ban on laptops and other large electronic devices that was put into place in March, senior DHS officials said Kelly ultimately concluded that the threats could be handled without an expansion of the ban.

“The good news is we found a way to raise the bar worldwide, but at the same time not inconvenience the traveling public,” said Kelly, who announced the new measures at a security conference at the Center for a New American Security.

DHS officials said they have been in “constant contact with our interagency, industry and foreign partners to address evolving threats” and had a shared goal of putting measures in place that would pose a minimum of disruption to the traveling public.

However, airlines and airports that do not comply with the new requirements could face repercussions, including a full ban on all personal electronics on board flights, even in cargo; fines and possible loss of their permission to fly to the United States.

Officials, however, said they expect the vast majority of airlines and airports to comply with the rules. Flights within the United States will not be affected, in part because airports here already use many of the enhanced security measures that are being called for.

DHS officials indicated they have been in touch with airlines and countries covered by the current ban and that “all of those countries had expressed an eagerness to comply so that those restrictions could be lifted.”

“We are standing ready to go in and inspect how they adhere to the new security restrictions,” the official said. “It is up to the carriers how quickly they want to move.”

It is not clear when the new measures will be put into place, but DHS officials said travelers might start to see changes as early as this summer. Not all the measures will be visible to the public, they said, though travelers might notice more bomb-sniffing dogs, more thorough screening of their carry-on bags and swabbing of devices for traces of explosives.

Wednesday’s announcement comes after months of debate over whether the United States should expand the ban on laptops and other electronic devices that it put into place in March for travelers from 10 airports in mostly Middle Eastern countries.

The ban was prompted by growing concerns that terrorists could conceal bombs in laptops and other similar devices.

In May, U.S. officials suggested the ban might be expanded to include direct flights to the United States from Europe. Later that month, in an appearance on “Fox News Sunday,” Kelly suggested he might go even further and extend the ban to all international flights in and out of the United States.

European officials raised concerns about potential new restrictions and sought more information about the threats that prompted talk of an expansion. European Union officials characterized a meeting last month in Brussels with top U.S. Homeland Security officials as productive but also urged officials to consider other ways to address the potential threat.

Industry groups in the United States and abroad said they were concerned about the economic implications of expanding the ban as well as the impact it could have on worker productivity.

In May, the head of the International Air Transport Association, which represents more than 270 international carriers, expressed serious concerns about the ban and urged leaders to consider other enhanced screening methods as an alternative.

Expanding the ban could cost $1.1 billion a year in lost productivity, travel time and “passenger well-being,” Alexandre de Juniac, director general and chief executive of the group, which represents 265 airlines, wrote in a letter to Kelly and Violeta Bulc, the E.U.’s top transportation official.

In all, 280 airports in 105 countries will be required to meet the heightened security standards, DHS officials said. Roughly 325,000 daily passengers on 2,100 flights could be affected.

DHS officials said one visible change could be the expansion of Customs and Border Protection’s Preclearance program, which is in place at airports in six countries: Aruba, the Bahamas, Bermuda, Canada, Ireland and the United Arab Emirates. Under the program, CBP officers screen international passengers traveling to the United States before they arrive.

Still, the announcement was welcome news for international carriers.

“Keeping our passengers and crew safe and secure is our top priority,” said de Juniac. “Today’s actions raise the bar on security. The aggressive implementation timeline will, however, be challenging. Meeting it will require a continued team effort of government and industry stakeholders. In particular, airlines and airports will need to be supported by host states during the phase-in of the new requirements.”