Iran summoned the UK envoy on Sunday to complain about his attendance at an "illegal" rally in Tehran to commemorate those killed in a Ukrainian airliner mistakingly downed by the country's military forces, Iranian Foreign Ministry's website reported.
"Today, Rob Macaire was summoned because of his unconventional behavior of attending an illegal rally on Saturday," the report said.
Britain said earlier that its ambassador in Iran had been briefly detained on Saturday, which Iranian media said was because he was inciting anti-government protests.