A proposal to allow some small pocket knives aboard US flights for the first time since the 9/11 attacks has been delayed.
The policy shift, which sparked opposition from consumers and flight attendants, was to take effect on Thursday.
The delay was announced by Transportation Security Administration (TSA) chief John Pistole.
He had said the change would free screeners to focus on other threats.
Pistole last month proposed allowing passengers to bring blades shorter than 2.36in and narrower than 0.5in in aircraft cabins.
Billiard cues, ski poles, and lacrosse and hockey sticks would be allowed in carry-on luggage.
But fixed blades, razors and box cutters would still have been banned.
The TSA said the rules would bring the US into line with international guidelines and offer a better experience for passengers.
But in a letter to staff, Pistole said the delay would allow for further consultation with aviation security experts, the BBC reported.