Ike Ekweremadu, 60, and Beatrice Nwanneka Ekweremadu, 55, were charged with conspiracy to arrange the travel of another person with a view to exploitation, namely organ harvesting, police said.
Ekweremadu is an opposition senator in the southern state of Enugu, and a former deputy Senate president.
Police said they were alerted to the alleged scheme after reports of possible crimes under the modern slavery law. The child involved has been moved to a safe location and work is underway to provide additional support.
The BBC reported that the couple appeared at London’s Uxbridge Magistrates’ Court, where the court was told that the child involved was a 15-year-old boy.
Prosecutors told the court that the attorney general’s consent was necessary to proceed with the case, the BBC said, and the couple were remanded in custody until their next court appearance on 7 July.
Neither Ekveremadu nor his wife could be reached for comment.