Sheikha Latifa has not been seen in public for 18 months, since she reportedly tried to flee Dubai.
The FreeLatifa campaign is now asking the United Nations to place pressure on the United Arab Emirates to act.
Her best friend Tiina Jauhiainen, who was part of the attempted escape, says on her capture the princess told armed men she preferred to be shot than be taken back home.
UAE authorities said in December that the reports about Sheikha Latifa were false and that she was living with her family in Dubai.
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