The actor opened up about the royal premiere during his appearance on Thursday's Jimmy Kimmel Live, recalling how he and his co-stars prepared to meet the Duke and Duchess of Sussex.
"Prince Harry and Meghan Markle came, and Beyonce was there, and Sir Elton John was there. And I was there, randomly," joked Eichner, who plays Timon in Disney's live-action remake. "And it was great, and we were all kind of nervous, even Beyonce."
"Really?" Kimmel asked. "They should be bowing to her!"
"That's true, actually. She's our American royalty," Eichner replied. "But what makes you nervous is in the days leading up to it, they email you a protocol of how you're supposed to greet Prince Harry and they're very intense about it. I'm not kidding."
"You're supposed to say, 'Your Royal Highness.' You can't speak until your hands are in a handshake with his. My plus one, my guest I brought with me, my very good friend Jared, they said he had to stand behind me and not speak unless he was spoken to," he continued, laughing. "I'm not kidding. I was like, 'Does that same rule apply to JAY-Z?' I have a feeling it doesn't."
Eichner confessed he "got really nervous" when it finally came time to meet Meghan and Harry, unsure of what to say (though he had also planned to talk to the duchess about both studying acting at Northwestern).
"'Your Royal Highness' sounds a little weird, and bowing feels weird. I don't even know what they want you to do, and in my head, I'm like, 'What do you call her?' I kept thinking she's Princess Markle, but that sounds like a character on Super Mario Brothers. They don't really call her that. Anyway, I completely freaked out, although they were very, very nice and totally chill and down to earth, and lovely," he said.
"She was really cool, and Harry was great too," he expressed. "They were very nice, lovely, beautiful looking people."
Beyonce's meeting with Markle made headlines on Sunday, with fans quickly analyzing footage of the encounter to discover what the women said to each other. Clips show Queen Bey addressing Markle as "my princess," before complimenting the former Suits star on her "beautiful" baby boy, Archie, and revealing that she and JAY-Z "love" her and Harry.
Funny enough, a source told ET that Meghan was "nervous" to meet the GRAMMY winner. See more in the video below.