A farmer who has lodged a £10,000 compensation claim for damage caused to his cornfield in the search for murdered eight-year-old Sarah Payne said yesterday his actions were "entirely proper".

A police source, who has visited the Payne family, said they had reacted with "disbelief" to the claim, but farmer Paul Langmead insisted that the cost of the damage could not be ignored.

The damage occurred in the cornfields adjacent to Kingston Lane near East Preston, West Sussex, where Sarah disappeared after playing there with her brothers.

Police have estimated that damage across approximately three acres of the fields was caused by the extensive searches but they are still awaiting clarification.

Yesterday, a middle-aged woman who refused to give her name issued a written statement at the Littlehampton farm run by Mr Langmead in which he pledged to donate any money received to the Sarah Payne fund.

"I am very upset that someone with Sussex police has seen fit to publicise the fact that I notified the police of damage to crops on my farm in the course of the search for Sarah Payne," Mr Langmead said.

"I and my farm staff have been deeply distressed by the tragic disappearance and murder of Sarah.

"However we cannot afford to ignore the fact that, through no fault of the police, many thousands of pounds of damage has been done to our crops during the course of searches for Sarah. It was entirely proper that the police should have been notified . . . so that they or their insurers can make their own assessment of the damage."

Meanwhile, as the hunt for Sarah's killers continued, her parents revealed they had received a letter from Tony Blair.

Sara Payne said the Prime Minister's letter, written from Hong Kong, was "very touching".

Her husband Michael said: "It's really nice to know these people do take an interest."

The couple are planning a memorial service at Guildford cathedral in Surrey to celebrate the life of their daughter, although no date has been set.

Mr Payne said: "It's going to be open to everyone, all the public and the police and Press who have all shown their support. We want everybody to celebrate her life.