A British mother whose young son is being held in Qatar by the family of her late husband based on the ruling of an Islamic court has said she will launch a legal appeal in a civil court to get him back.

Rebecca Jones, 43, has accused her ex-husband's family of "kidnapping" her 10-year-old son Adam on October 5 when they visited Qatar.

A Qatari Islamic court later gave custody of her son to the family of Adam's father, her late husband. "It is a kidnap, they're still holding him. They don't let him go out, he's not been going to school for nearly three months now," Ms Jones said in Bahrain this week.

Ms Jones has remarried since the death of her Qatari husband in a motorcycle accident in 2005, which may have decreased her chances of getting a favourable ruling under sharia, or Islamic law, legal experts said.

Ms Jones, who is originally from Sheffield in Britain and who is now based in Bahrain, said she intended to file an appeal to a civil Qatari court of appeal.