The new security measures, which European and U.S. officials said would begin taking effect within three weeks, could prompt additional screening time for the 325,000 airline passengers arriving in the United States daily.
"Inaction is not an option," Kelly told a news briefing, adding that he believes airlines will comply with the new screening. But he said the measures are not the last step to tighten security.
The decision not to impose new restrictions on laptops is a boost to U.S. and European airlines, which have worried that an expansion of the ban to Europe or other locations could cause significant logistical problems and deter some travel.
The United States in March imposed restrictions on laptops on flights originating at 10 airports in eight countries, including Egypt, Saudi Arabia, Kuwait, Qatar and Turkey. They came amid fears that a concealed bomb could be installed in electronic devices taken aboard aircraft. Britain quickly followed suit with a similar set of restrictions.
Kelly had been saying since April he thought an expansion of the laptop ban was "likely" and even said in late May the government could potentially expand the ban worldwide.
U.S. officials are requiring enhanced screening of personal electronic devices, passengers and explosive detection for the roughly 2,000 commercial flights arriving daily in the United States from 280 airports on 180 airlines in 105 countries.
Homeland Security officials told reporters they expected more than 99 percent of airlines would comply, a move that would effectively end the controversial electronics ban.
Airlines that fail to satisfy new security requirements could still face in-cabin electronics restrictions, Kelly said. "We expect all airlines will work with us to keep their aircraft, their crew and their passengers safe," he said.
European and U.S. officials told Reuters that airlines have 21 days to put in place increased explosive trace detection screening and have 120 days to comply with other security measures, including enhanced screening of airline passengers.
U.S. authorities want increased security protocols around aircraft and in passenger areas, expanded canine screening and additional places where travelers can be cleared by U.S. officials before they depart.
Since laptops are widely used in flight by business class passengers - who pay double or more than the average ticket price - the airline industry had feared expanding the ban could cut into revenue.
Airline officials told Reuters they are concerned about adding enhanced security measures to all airports worldwide that have direct flights to the United States rather than focus them on airports where threats are highest.
European airline groups said in a document reviewed by Reuters that if the threats are confirmed, the restrictions should be deployed to cover all EU departing flights, not just U.S.-bound flights.
Homeland security officials said Wednesday that those 10 airports can get off the list if they meet the new security requirements, but did not say how long it will take.
U.S. airline stocks were higher on Wednesday, with United Continental Holdings closing up 1 percent, Delta Air Lines Inc up 2 percent and American Airlines Group up 1.6 percent. None of the airlines immediately commented.
Kelly said last week he planned a "step by step" security enhancement plan that included short, medium-term and longer-term improvements that would take at least a year to implement fully. - Reuters
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