The husband of a British woman jailed in Iran says her family is "distraught" after Boris Johnson's comments about the case were used to discredit her.
A report on Iranian state television said the Foreign Secretary's suggestion that Nazanin Zaghari-Ratcliffe was training journalists when she was arrested last year had "voided" UK efforts to free her.
It has sparked fears she could now have her five-year prison sentence doubled.
Mrs Zaghari-Ratcliffe's husband Richard told Sky News it was now important that Mr Johnson "stands up very clearly for Nazanin and says she innocent".
He said: "She's a British citizen. All these political games and lies are unacceptable.
"I think it's really important he stridently tries to visit her. If that means going down and knocking on the door of the prison, I think that would be helpful.
"I think it would be good for me to go with him. Partly so I get to see my family, but also so he is clearly standing alongside us as a family. That's what I've been asking from the Government all along."
Mr Ratcliffe said his wife - who had travelled to see her family in Iran when she was arrested - had been visited by relatives on Wednesday, before state television reported Mr Johnson's comments.
"Certainly, her family were distraught," he said. "Who knows how she's feeling at the moment."
Despite Mr Johnson calling his Iranian counterpart earlier this week in a bid to clarify his comments, the country's state TV has since seized on the row.
An Iranian news report on the case said: "Boris Johnson's unintended confession confirming training some Iranian journalists by Nazanin Zaghari-Ratcliffe was a goof that the British government could not cover up.
"Some even are asking the foreign minister to resign."
It said Mr Johnson's remarks had "voided all efforts by the British government and media... who said Zaghari had been in Iran for humanitarian work".
Asked about Mrs Zaghari-Ratcliffe's case during a visit to the US, Mr Johnson told Sky News: "We have some difficult consular cases in Iran and we are working on all of them."
Both Mrs Zaghari-Ratcliffe's husband and her employers, the Thomson Reuters Foundation, deny the charity worker was teaching journalists in Iran, insisting she was on holiday with her baby daughter.
She was detained while attempting to fly home to London in April 2016
On Tuesday, as he faced a bruising parliamentary grilling over the row, Mr Johnson insisted there was "no doubt that Mrs Zaghari-Ratcliffe was on holiday in Iran… and that was the sole purpose of her visit".
He apologised if his comments had been "taken out of context" but denied any connection between Mrs Zaghari-Ratcliffe's most recent court appearance and his remarks.
Mr Johnson will travel to Iran before the end of the year, a trip in which he hopes to visit Mrs Zaghari-Ratcliffe in prison.
Mr Ratcliffe has said he hopes to join Mr Johnson on the trip in an effort to release his wife before Christmas.