UK PM: Britain will work to get full investigation into Iran plane crash

A spokesman for the British Prime Minister Boris Johnson has said that Britain will work with Canada, Ukraine, and other international partners to get a full, transparent investigation into the Ukrainian passenger plane which was downed outside Tehran airport last week, Reuters has reported.
The spokesman added that Johnson has called the arrest of the UK Ambassador to Iran at a protest on Saturday an unacceptable breach of the Vienna Convention, which needs to be investigated. "We are seeking assurances this will never happen again," he said. 
the Iranian Ambassador to the UK was summoned to the Foreign Office on Monday, in order for British diplomats to register their objections.