Boris Johnson apologised for the "distress and suffering" he had caused a British woman jailed in Iran as he faced renewed calls to resign.

The Foreign Secretary also retracted any suggestion that Nazanin Zaghari-Ratcliffe was in Iran in a professional capacity when she was arrested in 2016.

Mr Johnson told a Commons committee earlier this month that the mother of one was training journalists, which appeared to increase the threat of her five-year jail sentence being doubled.

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Mrs Zaghari-Ratcliffe was arrested and accused of plotting to topple the Iranian regime, which she denies, following a holiday.

Mr Johnson's fullest apology yet and retraction came against a backdrop of some Labour MPs shouting "resign" as he replied to questions in the Commons chamber.

Shadow foreign secretary Emily Thornberry, asking an urgent question, warned there had been a week of "obfuscation and bluster" from Mr Johnson.

She urged him to state "simply and unequivocally" that he got it wrong with his training remark, telling the Commons: "We know, from the evidence of Richard Ratcliffe, that when Nazanin was told of the remarks and saw how the Iranian authorities would exploit them she became hugely distressed and upset.

"So will the Foreign Secretary today accept the impact that his words have had, accept the distress that has been caused to Nazanin and apologise properly for that - not apologise for upsetting people, apologise for getting it wrong?"

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Ms Thornberry went on: "If it is a matter of pride that the Foreign Secretary is refusing to admit that simply he has made a mistake, well then I feel bound to say to him that his pride matters not one ounce compared to Nazanin's freedom."

Mr Johnson said he would repeat what he said last week, telling MPs: "Yes, of course, I apologise for the distress, the suffering that has been caused by the impression that I gave that the Government believed, that I believed, she was there in a professional capacity.

"She was there on holiday and that is the view."

One Labour MP could be heard saying: "Say sorry."

Mr Johnson continued: "I do apologise, I do apologise, and of course I retract any suggestion that she was there in a professional capacity.

"The honourable members opposite must have heard that from me about a dozen times."

Responding to Labour's initial question, Mr Johnson reiterated that his comments to the Foreign Affairs Select Committee should have been clearer.

He said: "I acknowledge the words I used were open to being misinterpreted and I apologise to Mrs Zaghari-Ratcliffe and her family if I inadvertently caused them any further anguish."

Tory former minister Sir Hugo Swire said "more than a faint whiff of opportunism hangs over this urgent question".