Max Clifford, the publicist, said he has been advising the couple through an intermediary believed to be a "close friend" of the Bramleys. He helped Mrs Bramley write an emotional plea published in several newspapers last week, but denied they were clients and said his advice was free. He suggested they take no money and speak to all the media.
The Bramleys, in hiding for four months, are believed to be ready to give up. The couple, both 35, vanished in September with Jade, five, and Hannah, three, after Cambridgeshire social services rejected their adoption application. Mr Clifford said: "Basically they are desperate. They're just very, very worried and frightened that they are going to lose the children."
A rival publicist, Kizzi Nkwocha, claims a friend of the family approached him about "marketing" the story.
Mr Clifford's involvement has angered Alan Barnish, chief executive of Cambridgeshire county council. He said he was "extremely disappointed", adding: "Our plea remains firmly that the two children are returned immediately in the interests of their safety and welfare. There can be no excuse for further delay."
Last week the council promised to leave the final decision on custody to the courts.
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