Kelly Rutherford faced one of the most heartbreaking days yet on Tuesday in her custody battle when she was ordered by a Manhattan judge to return her two children back to Monaco, where their father Daniel Giersch lives, after spending the summer with them in New York. Despite her upset, the scene inside the court remained civil, according to Daniel's lawyers.

"Mrs. Rutherford's sworn statement that she would return the children on 6th August, arriving in Europe on the 7th, was upheld today," lawyer Robert Michaels said after the hearing, adding that the children were handed over to their paternal grandmother following the ruling. "They're on their way to the hotel and then to the airport to go back to Monaco to be reunited with their father."

Kelly Rutherford was ordered to return Hermes and Helena to their father in Monaco on Tuesday Photo: Getty Images

He went on to confirm that there had been no changes made to the original custody order which "entitles Mrs. Rutherford free and consistent access to the children in Monaco and to have them come here and spend holidays and half the summer with their mother."

It is the latest twist in the bitter custody battle between Kelly and her ex-husband Daniel, who split in December 2008 when she was pregnant with Helena, now 6. A judge ruled in 2012 that it was in the children's "best interests" to live in Monaco with their father, who has been unable to enter the US since his visa was revoked that same year.

Kelly had her two children for the summer in New York Photo: Getty Images

Last month, Hermes, 8, and Helena arrived in the US to spend the summer with their mother – but Kelly refused to send them back, leading to claims of kidnapping by German businessman Daniel. As a result, Kelly and her legal team were ordered to appear in court on Tuesday, and she was told to send her son and daughter back to Monaco.

"I think everyone was very professional and well behaved in court," Daniel's attorney Ira Garr told Us Weekly. "The kids didn't seem to look like they missed a beat – they kissed their mother, they were happy to see their grandmother, and, by the way, they are two beautiful kids."

He added: "There was no scene. They hugged and said goodbye to their mother, and she said she will see them soon. They easily transitioned to their grandmother, who they love very much. Everything was done very civilly. They were told, 'Oh, you're going to see Poppa, and you're going with Oma.' The kids seemed fine."

Kelly on the other hand tells HELLO!, "What the judge did yesterday was shocking, illegal, and abusive to my children. Without any legal authority, a judge from the lowest ranking court in the state court system violated the highest ranking federal constitutional rights of my American citizen children."

She added: "I did my best to comfort the children, but there are no words to help children understand why a judge would be so cruel."

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