Dr Rowan Williams spoke out as Nazanin Zaghari-Ratcliffe's husband claimed his wife was being used as a "bargaining chip" in a broader diplomatic disagreement between London and Tehran.
Dr Rowan told Premier: "I think what's going to help most is if this case can be taken right out of political point scoring and I think religious leaders are well-placed to do that."
It was reported that the settlement of a £400 million debt was among a number of demands made by Tehran before it would free Mrs Zaghari-Ratcliffe, who was jailed for five years after being arrested last April and accused of trying to overthrow the Islamic Republic.
Concerned by reports that Mrs Zaghari-Ratcliffe is unwell, Dr Rowan continued: "The Iranian Government understands there is a role for religious leaders in public life and it's a role which has to do with fundamental moral issues.
"I think there some basic moral issues here which Christian leaders are in a good position to raise."
Earlier this month, the foreign secretary said Mrs Zaghari-Ratcliffe was in Iran to train journalists - an omission which might lead to her jail sentence being doubled.
Boris Johnson later apologised and retracted the statement.
Dr Rowan said current Archbishop of Canterbury Most Rev Justin Welby, Cardinal Vincent Nichols or a senior Vatican figure could be well-placed to help secure Mrs Zaghari-Ratcliffe's freedom.
He added: "If there were higher representation within the Roman Catholic Church, for example from the Vatican in the form secretary of state or someone like that, that would be wonderful.
"It would also be very powerful if there were some Muslim leaders who might be prepared to lend their voice to this, as well."
Click here to listen to Premier's Alex Williams speaking with Dr Rowan Williams: