British singer Joss Stone said she was "gutted" after being deported from Iran ahead of the latest leg of a world tour that has already taken her to Syria and North Korea.
She was held shortly after arriving at Kish airport, according to a post on her Instagram account, as authorities suspected she was planning to play a public gig.
Women have been banned from singing solo in public in Iran since the Islamic revolution of 1979. "We were aware there couldn't be a public concert as I am a woman and that is illegal in this country," she wrote, without specifying where or how she had hoped to play.
"So close yet so far, this moment broke a little piece of my heart," she wrote it the post, below a picture of herself wearing a headscarf.
Iran confirmed it had denied entry to the singer.
"Joss Stone and her entourage were refused entry to the territory for lack of required documents in accordance with the rules," Iran's state news agency IRNA quoted police officials as saying.