Sophie Turner Says Joe Jonas Is Illegally Refusing to Allow Kids to Return to England

Sophie Turner is at war with Joe Jonas over their 2 kids ... she says Joe is unlawfully keeping their children in New York City and she wants them "returned" to England with her.

Sophie says in April, 2023, the family made England their "permanent home," and regularly discussed their desire to raise the kids in the UK, and for the kids to attend school there.

She says they felt England was a safe place to raise kids, and they were both down with the plan. She had a lengthy passage in her legal docs, outlining all of the activities in which the kids have engaged in England.

She says "with some hesitation," she and Joe agreed the kids would stay with Joe while the Jonas Bros toured the U.S., because she was busy shooting a "very intense," time-consuming series.

Sophie says the agreement was that in September, when she finished filming, she would return to New York, to "collect the children and return home to England."

This past Sunday, Sophie and Joe met to talk about their separation, and she reiterated her desire to take the kids to England that week. Joe was in possession of the kids' passports, and "refused to return the passports to the Mother and refuses to send the children home to England with the Mother."

The Messenger was first to report the lawsuit.

Based on Joe's alleged refusal, she filed these legal docs in federal court, citing the Hague Convention -- an international treaty -- which deals with child abduction across country lines.

She's asking for a court order demanding that Joe produce the passports and return the kids to her.

Don't forget, we reported that the 2 sold their Miami home last month, BTW ... and were planning on moving to England, beginning their search for a spot overseas last December -- touring a couple of spots, too.

Sophie argues they've been living in the UK for 5 months now, and even sold the Miami home the month before he filed.

BTW ... Sophie gets into why they split. She says they had an argument on August 15 and Joe filed for divorce Sept. 1. She found out September 5 through the media. She adds they had both agreed the kids would follow her to England in Sept., but on Sept. 19 Joe's attorney contacted her people and said the kids would not be returning to England.

We reached out to Joe's camp ... so far, no word back.

Do you think the Sophie Turner/Joe Jonas divorce war will get uglier? Vote below.