"She opened my passport and saw 'Lindsay Lohan' and started immediately apologizing, but then said, 'Please take off your headscarf,'” the 30-year-old actress said.
In the clip shared by "Good Morning Britain," Lohan didn't say whether the woman was an airline, airport or security employee of any kind, though a representative for the actress told ABC News it was somebody at the security checkpoint right before passengers put their luggage through the X-ray system.
In response to a request for comment, an airport spokesperson told ABC News, “Heathrow respects the cultural and religious needs of all passengers traveling through the airport. We work hard to provide our passengers with great service while ensuring everyone remains safe and secure.”
Lohan said of the request, "I [took it off], it's OK."
She continued: "But what scared me was in that moment, how would another woman who doesn’t feel comfortable taking off her headscarf feel? That was really interesting to me."
Lohan couldn't speak to why she was stopped, but said "it was jarring" and that she had never been stopped before.
"It was strange," she said. "I'm from New York, I'm born and raised there so, I was a little intimidated."
The "Mean Girls" star added that actresses like Audrey Hepburn used to wear scarves on their head and that "my red hair doesn't exactly not stand out. ... I was doing it because I was leaving Turkey and out of respect for certain countries that I go to ... when I see certain people I feel more comfortable acting the same way as the other women, that’s just a personal respect issue for me that I have."
According to British travel regulations, passengers wearing headgear for religious reasons have the right to "ask for it to be checked using a hand-held scanner" so they don't have to remove it.
When asked earlier in the interview if she would convert to Islam, she replied, "I do study [the Quran], nothing is confirmed yet."
Lohan called the faith a "solace" and said she was studying other faiths as well. She added that her sister is Buddhist and that any religion is a personal belief. "I don't want to speak on something I haven't finished yet," she said, adding the faith feels "like it's a family to me ... it calms me."
Asked about President Donald Trump, Lohan said, "At the end of the day, he is the president right now. So, what’s the point of picking on someone instead of just seeing what they’re capable of, or not capable of," though she added that she disagrees with certain "policies."
"People are making it overly dramatic," she said. "I do think his Twitter needs to be taken away."
ABC News' Joseph Simonetti contributed to this report.