U.S. anti-terrorism officials met for four hours Wednesday in Brussels with their European counterparts who are resisting a proposed expansion of a laptop ban in airline passenger cabins. U.S. officials called the threat critical but stopped short of any new action. The dialogue was robust and collaborative, according to a U.S. senior administration official speaking to reporters at a briefing. The U.S. delegation, led by Homeland Security Department Deputy Secretary Elaine Duke, wanted to hear European Commission concerns that a ban may be disruptive to the aviation system, said the official, who gave the briefing on condition that he not be identified. No decision has been made on whether to expand the current ban imposed on March 21, which applies to 10 airports in the Middle East and North Africa, the official said. Passengers on flights from those locations to the U.S. can’t carry laptops, tablets or other electronic devices larger than a smartphone in aircraft cabins. They must be stowed in checked bags or transferred to the cargo area of the plane before departure. While no specific action was announced, the U.S.’s unwillingness to back down combined with weeks of warnings of impending action have left the impression that some sort of expansion is inevitable. “We are actively preparing contingency plans to support our customers and employees in the event we need to make any policy or procedure changes to comply with new government security directives,” United Airlines spokeswoman Erin Benson said in an email. “In the meantime, we continue to follow all existing policies.” Previous story: U.S. Considers Expanding Airline Laptop Ban Beyond Europe The International Air Transport Association, a trade group representing 265 carriers that has been critical of expanding the ban, said the meeting was welcome “but industry needs to be involved.” A wider ban could cost travelers more than $1 billion, the group said earlier Wednesday. The European Union had earlier pressed the U.S. to refrain from barring electronics. EU Home-Affairs Commissioner Dimitris Avramopoulos, who participated in the meeting Wednesday, on Tuesday said: “We are very much concerned.” The talks will continue next week in Washington, according to a statement by the European Commission. The timeline for a possible expansion of the ban to Europe or other nations won’t be based on the timing of future meetings, according to the U.S. official. “At the meeting, both sides exchanged information on the serious evolving threats to aviation security and approaches to confronting such threats,” the DHS and European Commission said in a joint statement. “Participants provided insight into existing aviation security standards and detection capabilities as well as recent security enhancements on both sides of the Atlantic related to large electronic devices placed in checked baggage,” they said in the statement. Duke, who was accompanied by the Transportation Security Administration’s acting chief, Huban Gowadia, met with European Commissioners Avramopoulos and Violeta Bulc, according to the commission statement. The meeting, a portion of which was conducted in secure facilities, allowed U.S. representatives to discuss specifics about the threat and how it is evolving, according to the U.S. official. Details of intelligence or how bombs could be concealed in devices weren’t revealed in the briefing with reporters. Russian Visit The Washington Post and other news organizations on Monday reported that President Donald Trump gave Russia’s foreign minister and ambassador closely held intelligence obtained from a U.S. partner about an Islamic State terrorist plot to use laptops as possible weapons aboard commercial aircraft. The U.S. official addressed one of the concerns being raised by airlines and aviation safety groups: the potential for raising the risks of fires by placing more volatile lithium-based batteries into the cargo holds of airliners. The DHS, working with the U.S. Federal Aviation Administration, has sent carriers safety guidance for how to handle the influx of devices into the cargo areas, the U.S. official said. While bulk battery shipments and spare batteries may be a hazard, devices containing batteries are a lower risk. The FAA and DHS are conducting additional tests on the devices, but officials believe the fire danger can be limited, the official said. While declining to discuss specific intelligence, the U.S. is basing its consideration of an expansion on the the evolving threat from terrorists, according to the official. Southwest Airlines Co. Chief Executive Officer Gary Kelly said the carrier needed to work with DHS to limit the risks. “We have a threat and we have to be very mindful of that,” Kelly said. Southwest hasn’t been affected by the ban or discussions about its expansion to flights from Europe because it has no operations across the Atlantic Ocean. Kelly spoke in Phoenix at the company’s annual meeting. “Eventually I’d hope we could work to a solution that doesn’t ban laptops in the cabin,” Kelly said.