The husband of Nazanin Zaghari-Ratcliffe, a British woman imprisoned in Tehran, said he is in limbo waiting for news of his wife's release but has not given up hope.
Richard Ratcliffe has spent his second festive period without his spouse or three-year-old daughter, Gabriella, but described the situation as "a lot more positive" than last year.
He had hoped she would be home in time for Christmas Day or Boxing Day, but said that this "big happy news didn't happen" and he is currently in "waiting limbo".
"I think it is a question of when, not if," he said when asked by the Press Association if he is still optimistic about the release of his wife, who has been detained for more than 634 days.
"We put a lot of time into having her home for the Christmas holiday period (up until January 6), and if that doesn't happen my worry is there must be something blocking and more complicated than we realised.
"With each day that goes past it is another day that she has not been released, and so I need to be realistic about that.
"But I haven't given up hope that this holiday period still could deliver a late Christmas."
Mother-of-one Mrs Zaghari-Ratcliffe was arrested in 2016 during a visit to show her baby daughter Gabriella to her parents.
She is currently serving a five-year sentence over allegations, which she denies, of plotting to overthrow the Tehran government.
Gabriella is being looked after by Mrs Zaghari-Ratcliffe's parents in Tehran, and other than over Skype, Mr Ratcliffe, from Hampstead, north-west London, has not seen his daughter for more than half her life.
Last week, Mrs Zaghari-Ratcliffe's sister-in-law Rebecca Jones said her lawyer had discovered that on a judiciary database, her case had been marked as eligible for early release.
Mr Ratcliffe also said there have been mentions of a second court case coming out of Iran, but that the idea of release is also "being talked about".
He said his wife was "fairly upbeat" until December 23 when her release did not happen as previously thought, and that she was "very low" on Christmas Eve.
On Christmas Day he said Mrs Zaghari-Ratcliffe and the other prisoners had a celebratory meal of roast chicken and read out passages from the Quran and Bible.
He also said his wife made a Christmas pudding and explained to fellow inmates that normally it is covered with brandy which is then set alight.
She celebrated her 39th birthday on December 26 by cooking for her fellow prisoners, and was given presents which included coffee.
"On her birthday what we did is we bought a cake and her family in Iran bought a cake, then across Skype Gabriella blew out the candles," he added.
Mr Ratcliffe said on Christmas Eve his daughter and his wife's family were invited to the home of Nicholas Hopton, the British Ambassador to Iran.
"She had a very nice time, he gave her a colouring book and then played around the Christmas tree with his children - they had Christmas cake and sang some carols," he added.