The 34-year-old singer, who referred the country as "half Spanish, half English", despite it being a British territory, said sorry for commenting on their heritage.
"If I offended anyone tonight in Gibraltar about their heritage I'm sorry. I had no intention of doing that. I come in peace! I only bring love (sic)," she tweeted.
Many fans and locals also took to the micro-blogging website to voice their anger at the mistake, with one user noting they are "most certainly not Spanish".