Dec Donnelly tried to shake hands with Prince Charles when he collected his OBE.
The television presenter and his presenting partner Ant McPartlin were awarded the honour recently but Dec admitted he made a faux pas when collecting his award for services to broadcasting and entertainment.
He revealed: "You know, they come and tell you the protocol. You come out and you stand there next ... and then they say your name and on your Christian name, you move forward, you take two steps. You turn, you bow from the neck not from the waist and then you go forward and Prince Charles will pin the thing to you.
"And I just got really excited and forgot it all ... I put my hand out to shake his [Prince Charles'] hand and it's like he's got this thing in his hand so I was like, OK I'll just put that back there."
The pair went up to collect the honour alongside other receipients and were split up as the names were listed alphabetically, with Ant admitting it was "weird" to be apart.
Ant said: "We went together and they called you up; they call your names differently so Dec went first for the first time [ever]."
Whilst Dec added: "I went first! They do a little role call backstage and read out your names alphabetical so I went first. I was near the front of the queue and you [Ant] was about 10 people behind me."
Before Ant quipped back: "I didn't know what to do! It was really weird; there was like 10 people in front of me and I was like [waving]. 'Are you alright? Are you nervous? Good luck!'"
Whilst in the queue, the duo met other honourees including the man who invented Shazam and a glass blower who makes instruments for medical experiments.
Speaking to host Dermot O'Leary on Thursday evening's (23.03.17) episode of The Nightly Show, Dec said: "The guy behind me invented Shazam, which was amazing, so that was quite good conversation. More interesting than being next to [Ant] in the queue!"
Whilst Ant added: "The guy next to me blew glass for medical experiments. And we feed testicles to celebrities so you know, we've all got at a skill in life."
Tagged in Ant And Dec Declan Donnelly Ant McPartlin