Caroline Hawley, BBC

A British woman jailed in Iran for almost a year has spoken of the pain of separation from her family in a poignant Christmas message written in her cell.

"At a time when we should be connected, we find ourselves alone, down, dejected," Lindsay Foreman wrote in a poem entitled A Sad Voice From Evin Prison - A Christmas Poem.

A recording of her reading the message to her son on the phone from a noisy prison corridor has been shared with the BBC. It is the first time her voice has been heard publicly since her arrest.

She spoke of a "family torn apart" and said that grief "has made a home from the hole in our heart".

Ms Foreman, 53, said she wrote the poem for her family "and for anyone who has lost someone and when Christmas may not be such a happy time".

She and her husband Craig, from East Sussex, were on the trip of a lifetime, by motorbike, from Spain to Australia when they were arrested by Iranian authorities in January. The couple has been accused of espionage – charges the family say are "ludicrous".

They had visas for Iran, a tour guide and a pre-approved itinerary.

Ms Foreman had been asking people along the route what constitutes a good life, and those questions appear to form the basis of the regime's accusations against the couple.

They are currently being held separately in Iran's notorious Evin jail in Tehran, where Nazanin Zaghari-Ratcliffe was previously imprisoned.

Their family say the cells are overcrowded, unsanitary and vermin-infested, with inadequate washing facilities and hygiene supplies.

"They are in unimaginable conditions," Ms Foreman's son Joe Bennett told the BBC, describing rats running around as they cooked.

He said the couple were not receiving enough food and were losing weight.

Mr Bennett's stepfather, Craig Foreman, is said to be suffering constant dental pain but has not been allowed to see a dentist.

After going on hunger strike last month, the couple are now being allowed almost daily phone calls with their family.

But Mr Bennett says that, despite her attempts to put a brave face on for him, he has heard his mother crying and begging to get home.

Both his mother and step-father are being "slowly broken" and in "growing distress", he says.