The parents of brain-cancer patient Ashya King say they will not return to the UK until they get assurances from authorities about what will happen to their child.

Brett and Naghmeh King sparked an international manhunt when they removed their five-year-old son from Southampton General Hospital on August 28 without medical consent.

Ashya has now completed a course of treatment at the Proton Therapy Centre (PTC) in Prague. "He's communicating with us, because he can hear us and he can see us. He's so much, so much better now and we're really happy with him, the fact that he's saying a few words as well," Mrs King said."He's improving each day."

Speaking from the family's home in Spain, Mr King said: "It's all been worth it."

He said Ashya could now walk with support, whereas previously "it was almost like we were carrying him".

But the family fears Ashya could be removed by British authorities if they return to the UK. "If they ever try to take Ashya away that would kill us," Mr King said.

"Until things are established with what's going to happen with Ashya, we feel too scared to return."

He said the family is in contact with an MP who was seeking information from child protection and health services on their intentions.

"There's a real fear that we have, not regarding us being arrested again, but regarding Ashya," Mr King said. "We don't really know what social services and the NHS have in store for us …

"We've heard so many stories when families go back, they think it's safe to go back, the social services get involved. They take the child away. And then they give a gagging order for the parents so they can never explain their story."