The US announced Wednesday it would implement tough new security rules for all airlines flying into the country, but held off from a threatened expansion of its carry-on laptop ban.

Secretary of Homeland Security John Kelly said evolving terror threats made it imperative to raise security standards for airlines from all countries, rather than take a piecemeal approach on personal electronics.

"We cannot play international whack-a-mole with each new threat. Instead, we must put in place new measures across the board to keep the traveling public safe and make it harder for terrorists to succeed."