According to the report, the same individual is the subject of a seperate investigation relating to a private bank.
Britain's Foreign Office has said that it is "currently investigating the reported sentencing".
Iran has jailed a number of individuals for allegedly acting as spies for Western powers and Israel, including dual nationals.
Almost two years ago, British-Iranian citizen Nazanin Zaghari-Ratcliffe was arrested for allegedly plotting to topple Iran's government.
The Thomson Reuters Foundation employee remains in custody, having served a third of her five-year jail sentence for sedition.
Although Zaghari-Ratcliffe is now eligible for release, her family said last week that they have received no information from Tehran about why she is still in custody.
The case has become highly politicised, especially after a careless blunder by British Foreign Secretary Boris Johnson in December in which he stated that Zaghari-Ratcliffe had been training journalists in Iran - something the Thomson Reuters Foundation and her family have strongly denied.
This has been used by the Iranian authorities to help justify the new charges and may contribute to her potentially lengthened sentence.
An online petition for her release has collected almost 1.5 million signatures.
