The Foreign Office has said it is "deeply concerned" about a British academic accused of spying in the United Arab Emirates after his wife called on the Government to say he was innocent.
Matthew Hedges, a 31-year-old PhD student at Durham University, was held at Dubai airport on May 5 after flying in to interview sources about the country's foreign policy and security strategy.
He has been held in solitary confinement for almost six months, his family said, and they were concerned he will not have a fair trial as he has had limited access to his lawyer.
His wife, Daniela Tejada, 27, called on the Government to deny he was spying for them.
In response, a Foreign Office spokeswoman said: "We remain deeply concerned about Matthew Hedges and are in regular contact with the Emiratis regarding his health and wellbeing.
"We continue to press for consular access. We also remain in close contact with Matthew's wife, Daniela."
Earlier, Ms Tejada said: "I no longer know what to do to get Matt out of prison in the UAE.
"I am calling on the UK Government to clarify publicly that Matt is innocent of the charges and that there have been many falsehoods said about him.
"It is the duty of the Foreign and Commonwealth Office to protect their citizens abroad.
"This horrifying situation has been going on for far too long."
Ms Tejada said her husband, who is from Exeter, only met his legal representative for the first time at court last week.
She said: "The entire hearing was in Arabic, with only the questions directed at Matt being translated into English.
"It has now been confirmed to us that Matt was told he was being charged with gathering information and sharing it with a foreign agency - the UK Government."
He will be back before the court on October 24 after the case was adjourned to allow him to prepare his defence.
She said: "The prosecution has therefore had over five months to come up with a case for trial and Matt's court-appointed lawyer has been given two weeks with no further access to Matt.
"To call this a fair judicial process is, to say the least, highly inaccurate.
"Matt has never been allowed to speak about his case with anyone.
"He was never given the opportunity to look for a lawyer to represent him, especially as it was not known what he needed to be represented for.
"The charges against Matt are false and unsubstantiated, as is the purported evidence to support them.
"Matt continues to be denied appropriate medical care for his mental health and remains in solitary confinement."
According to a profile on the Durham University website, Mr Hedges's research includes Middle Eastern politics, the changing nature of war, civil-military relations and tribalism.
Amnesty International UK also called on the Government to speak out on Mr Hedges's behalf.
The group's foreign affairs spokeswoman Polly Truscott said: "Matthew wouldn't be the first person to be arrested in the UAE on baseless grounds and to be detained for a long period without access to a lawyer.
"If he's been charged with espionage simply for having conducted academic research into the country's security services, he should be released immediately."