Chad's president has indicated as many as 10 of the 16 Europeans held in the child abduction scandal may be freed.
The French charity said they were trying to give the children a better life
President Idriss Deby told reporters he hoped "the journalists and also the (air) hostesses will be released".
The UN found most of the 103 children stopped from leaving Chad lived with a close relative and were not orphans.
Six workers for French NGO Zoe's Ark are charged with kidnapping. Three French journalists and seven Spanish air crew are charged as accomplices.
Mr Deby said justice would have to take its course.
"I can't force the hand of Chadian justice, there is a procedure," Mr Deby told reporters in the eastern town of Abeche.
A joint report by two UN agencies and the Red Cross said most of the 21 girls and 82 boys, aged one to 10, came from villages in Chad near the Sudan border.
Zoe's Ark claimed the children came from Darfur, on the Sudanese side of the border, but the UNCHR and Red Cross report says 85 of the children came from the Adre and Tine border areas of Chad.
UNHCR spokeswoman Annette Rehrl in the Chadian border town of Abeche told BBC News the children were most probably Chadian but could also be Sudanese as both ethnicities lived on both sides of the border.
Most of the children were aged three to five and were too young to be asked about their nationality, Ms Rehrl added, saying it would take time to find and ask their parents.
The agencies said some of the children had been treated for small injuries, but none appeared to be suffering from serious health conditions.
The report said the agencies would "continue their efforts to find a quick and appropriate solution for each one of the 103 children to allow them to go back home, join their families and live a child's life".
Fears for EU force
The affair has caused a diplomatic storm between Chad and its former colonial power, France, although France has condemned the charity's activities.
French President Nicolas Sarkozy phoned Mr Deby requesting the release of the three journalists on the grounds that they were not complicit in the alleged abductions.
Mr Deby said he would do everything in his power to secure their release, Mr Sarkozy's office said.
Correspondents say there have been worries the affair will damage relations - France is the main backer of a European Union peace force due to go to the region in the next few weeks to protect Darfur refugees.
People in Abeche came out onto the streets on Wednesday in protest at the alleged kidnappings.