Boris Johnson has said he is sorry if his words about a British-Iranian woman caused anxiety to her family.
The foreign secretary had been criticised for saying Nazanin Zaghari-Ratcliffe, in prison in Iran, had been training journalists there.
A charity said the remarks could worsen her sentence. She had been in Iran on holiday when she was arrested, it said.
Mr Johnson told MPs he was sorry if his words had been so taken out of context as “to cause any kind of anxiety”.
Mr Johnson said the UK government had “no doubt” she was on holiday when she was arrested in 2016.
Mrs Zaghari-Ratcliffe is serving a five-year sentence for allegedly plotting to topple the government in Tehran, although the official charges have never been made public.
Her husband said Iranian officials were using Mr Johnson’s statement to justify extending his wife’s sentence.
Richard Ratcliffe maintains his wife’s innocence, saying she was in Iran visiting family when she was arrested last year.
She was summoned to court on Saturday 4 November, where Mr Johnson’s comment was cited as new evidence as to what she was doing in Iran.
Mr Johnson said his previous remarks to the Commons Foreign Affairs Select Committee “could have been clearer”
Speaking in the Commons, he said: “My point was that I disagreed with the Iranian view that training journalists was a crime – not that I wanted to lend any credence to Iranian allegations that Ms Zaghari-Ratcliffe has been engaged in such activity.
“I accept that my remarks could have been clearer in that respect, and I’m glad to provide this clarification.”
Later, when MP Layla Moran asked him if he would apologise to Mrs Zaghari-Ratcliffe’s family, he said: “Of course I am sorry if any words of mine have been so taken out of context and so misconstrued as to cause any kind of anxiety for the family.”
He said he did not believe his comments “had any impact on the judicial process” in Iran.
Caught in the middle
By Rana Rahimpour, BBC Persian Service:
President Rouhani says Iran’s judiciary is entirely independent of his government.
Indeed, a number of members of his inner circle have family members in jail, with seemingly little they can do about it.
The judges are actually far more closely linked with the powerful Revolutionary Guards, who not only share many of their geopolitical objectives, but often have close personal and family links.
Can President Rouhani exert any meaningful pressure on the judiciary? Possibly yes.
But recent moves in the case of Mrs Zaghari-Ratcliffe, most notably her being taken for retrial a month ago, suggest her fate is being decided by others.
Just as she had applied for an early release, new charges were found – including accusations she was helping to overthrow the government.
This leads to the suspicion that the Revolutionary Guards is using her as a pawn in some wider game.
Exactly what their end goal may be is anyone’s guess, but Mrs Zaghari-Ratcliffe is caught in the middle and paying a heavy price.