Kelly Rutherford has hit out at a federal court decision to deny her custody of her children.

The former 'Gossip Girl' actress -- who has been involved in a six-year legal battle with ex-husband DANIEL GIERSCH over custody of son Hermes, eight, and daughter Helena, six -- has expressed her frustration at her case being thrown out of court earlier this week, resulting in her kids being sent back to Monaco to live with their father.

In a statement, Kelly's attorney Wendy Murphy questioned the federal court's decision to rule the matter a state court matter, citing the Hague Convention, which protects children in matters of international custody and adoption.

The actress, 46, also insists that the children, nor their parents, are citizens of Monaco, where the custody battle is ongoing.

Kelly's attorney continues: ''So why would Monaco want to restrain the children from living in their own country?''

The attorney also points out the contradiction in treatment between Kelly's children and non-US citizens.

The statement to UsMagazine.com said: ''New York is a 'Sanctuary City', meaning non-criminal illegal aliens cannot be forced to leave.

''How on earth could a judge from the lowest ranking court in the state court system find it proper to grant American citizens less legal protections, in terms of the right to LIVE in the United States, than people who are not citizens and have no right to be here?''

Meanwhile, Daniel has hit back at Kelly's claims she didn't send them back to Monaco on August 6, as ordered by the court, because they were ''panicky'' about going to live with their father.

His lawyer said: ''There was no scene. They were fine ... smiling broadly.

''When they left the courtroom they were happy and showed no signs of missing their mother.''