The TSA said in a statement on Monday it will seek additional input from a federal advisory committee that includes aviation interests, passenger advocates and law enforcement experts before enacting the policy.
Airline passengers were to be permitted to carry knives with small blades, including pocket knives, starting on Thursday. The TSA did not give a possible new date for when the policy could take effect.
Knives and many other sharp objects were banned from flights after 9/11. Under the TSA plan, knives with blades measuring 2.36 inches or shorter and less than half an inch wide would be allowed in airline cabins as long as the blade is not fixed and does not lock into place.
The TSA came under fire from lawmakers, flight crews and others who worried that the change posed a danger for crewmembers and passengers. Some airlines oppose the policy.