A former journalist with the British Broadcasting Corporation’s Persian service was arrested in Iran on Wednesday, Iranian activists outside the country reported, just as Iran’s foreign minister embarked on a trip to Britain, the first such visit in more than a decade.

The former journalist, Bahman Daroshafaei, a dual citizen of Britain and Iran, was taken into custody for undisclosed reasons in Tehran, where he had been working as a translator, according to an account on Iranwire, a news service founded by expatriate Iranian journalists.

The arrest may have been intended by hard-line factions in Iran, which are suspicious of improved ties with the West, to embarrass Foreign Minister Mohammad Javad Zarif, who has been seeking greater engagement.

By The New York Times