The British parents who sparked a major manhunt by taking their seriously ill son out of a hospital last week have asked a Spanish court not to extradite them to the United Kingdom, a judicial source said on Monday.

Brett and Naghemeh King are wanted in the United Kingdom after removing their son, Ashya, 5, who is suffering from a brain tumor, from Southampton General Hospital in southern England on Thursday, raising fears his life could be at risk.

"They have said they don't want to be handed over to the British authorities," the source told Reuters.