Two Americans charged with kidnapping children following Haiti's devastating earthquake will be released by Thursday at the latest, said one of their lawyers, Aviol Fleurant.

The announcement was made after the judge in Haiti ruled the case would be closed by the end of this week because there were no criminal grounds to pursue it.

Laura Silsby and Charisa Coulter were the last of 10 members of a Baptist missionary group still in Haitian custody over an attempt to take 33 children to the neighbouring Dominican Republic without government permission.

Fleurant said Silsby and Coulter were questioned Tuesday at the prosecutors' office in the presence of a U.S. consular official and a representative from a Haitian human-rights organization.

The other eight Americans charged in the case were released a week ago and returned home.

All 10 Americans were arrested 29 January as they sought to take a busload of children across the border into the Dominican Republic. The Baptist missionaries from the New Life Children's Refuge sought to take the children without government authorization.

They at first presented the kids as quake orphans but it quickly emerged that many of the children still had parents alive, who agreed to the kids being moved.