"I really don't want to offend anyone's beliefs or impose anything on anyone and it was mistaken to do it," Portman told "Access Hollywood" in an interview broadcast Monday.
The 23-year-old Israeli-born actress and her crew were confronted by ultra-Orthodox Jewish worshippers last week while filming the scene with Israeli actor Aki Avni. The incident underlined the sensitivity of the site, a remnant of the biblical Jewish temples, the holiest place where Jews can pray.
The site is controlled by strictly observant Jews. Male and female worshippers are separated by a barrier perpendicular to the wall, following Orthodox Jewish rules forbidding casual contact between the sexes.
"As soon as it offended people, we moved," Portman said. "We had a very hectic work schedule, so we weren't thinking. We shouldn't have done it."
"Access Hollywood" also aired an interview with Antonio Banderas, who explained why his wife, Melanie Griffith, arrived at the Academy Awards show Sunday with a broken foot.
Banderas said Griffith "was a little upset with her performance and she kicked in the door" while playing Roxie Hart in the musical "Chicago."
Said Griffith: "I was singing and I am not a singer."