A representative for an American couple cleared Sunday by a Qatari appeals court of wrongdoing in the death of their 8-year-old adopted daughter but blocked from leaving the country has blasted a continued travel ban against them as "institutional kidnapping."

Eric Volz told The Associated Press that Matthew and Grace Huang hope to leave the Gulf nation Monday but have been told by the U.S. government that a number of procedural steps must still be completed before they can depart.

A Qatari appeals court on Sunday overturned a child endangerment conviction against the Huangs over the death of daughter Gloria and said they were free to leave the country. They were stopped at the airport as they tried to depart hours later.

Qatari officials have not commented.