Officials said Khan was intercepted by CISF security personnel at the airport terminal after they detected four live rounds of .32 bore bullets in his baggage during scanning.
He was later questioned by officials over carrying the prohibited ammunition to which expressed ignorance.
Officials said he then produced his arms license after which he was allowed to proceed.
Additional Director General of CISF (Airport sector) O P Singh confirmed the incident.
"The minister has been allowed to travel to Lucknow after he produced his arms license. However, the bullets have been seized," he told PTI.