American secret service agents asked a Royal Navy warship if it would mind pointing its missiles in another direction, after they became concerned they were targeting Michelle Obama.
HMS Edinburgh had its Sea Dart missiles pointed at a hotel room in Cape Town where Mrs Obama was staying as part of a foreign tour.
According to the Portsmouth News, the secret service told sailors: "you can't point those guns at the First Lady".
But the Mrs Obama's protection had no reason to worry, as the missiles were blanks and were just in place as part of a ceremony.
HMS Edinburgh was visiting South Africa on June 24 in order to repatriate the body of one of its sailors, Sara Hellawell, who was found dead in her cabin.
A Royal Navy spokesman said: "This involved the drill missiles being on their launcher. American officials did visit the ship. They simply wanted to know if the missiles were live. When it was explained that they were drill rounds they went away content."