The parents of young cancer patient Ashya King have described how the boy struggled for breath with joy as he was reunited with his family in a Spanish hospital.

Brett and Naghmeh King saw their five-year-old son yesterday for the first time since they were arrested on Saturday, having fled from Southampton General Hospital in search of treatment.

Leaving through a back door of the Materno-Infantil hospital in Malaga with his older son Danny, Mr King spoke of the first moments he saw his son.

''He couldn't breathe he was so happy,'' he said. ''He was so pleased to see us. We're trying to be hopeful.''

Mr King, who said he will meet a cancer specialist today, added: ''He's not in such a good state as when we left him - spirit depressed since his parents left him.

''We'll do what it takes. Not much else to do.''

Hospital officials said Mrs King was expected to stay with Ashya through the night, amid reports the Kings would not be permitted to remove the child from the premises. A Materno-Infantil spokeswoman said local authorities had received notification from British officials that the parents should not be allowed to take the boy away.

The reunion initially appeared to be in doubt when Mr King claimed he would be barred from visiting the child after Ashya was made a ward of court. But it was established that those proceedings do not stop the couple seeing him.

Mrs King said she had been ''crying and crying'' as she described the torment of being unable to help her son from the jail cell near Madrid where she and her husband had been detained since they were arrested on Saturday.