TEHRAN (Dispatches) -- The British ambassador to Tehran has left Iran after being detained by Iranian authorities last week for attending riots, media reports said on Wednesday.  
Rob Macaire was detained for on January 11 after attending protests following the accidental downing by Iran’s air defenses of a Ukrainian passenger plane.
Iran’s official IRNA news agency said the diplomat had left after being given what it described as "prior notice.”
The British Foreign Office insisted that Macaire’s trip to London was "routine, business as usual” and was planned before his arrest.
"It is quite normal for our ambassadors to come back to London to have meetings here,” a spokesman said.
Iran’s Foreign Ministry summoned the British ambassador to protest his unconventional behavior, arguing that it ran counter to the 1961 Vienna Convention on Diplomatic Relations.
The British ambassador was told that the UK government should give an explanation for the incident.
The Iranian Judiciary has referred to Macaire as "persona non grata” and demanded that the ambassador be expelled over his unacceptable conduct, but noted that the final decision on the matter rested with the Foreign Ministry.
"The fact that the UK ambassador to the Islamic Republic attends an illegal gathering, takes photos and videos of the event and plays a provocative role is totally unacceptable,” Gholamhussein Esmaili, the Judiciary’s spokesman, said during a press briefing on Tuesday.