Iranian ambassador summoned after 'unacceptable' arrest of British ambassador in Tehran
Iran's ambassador to the UK has been summoned by the Foreign Office in response to the "unacceptable" arrest of the British ambassador in Tehran, Downing Street said.
The UK Government will tell Iran's ambassador in London it has "strong objections" to the arrest of the UK's top diplomat in Tehran.
The Prime Minister's official spokesman said: "In relation to the arrest of the UK's ambassador over the weekend, I would say this was an unacceptable breach of the Vienna Convention and it needs to be investigated.
"We are seeking full assurances from the Iranian Government that this will never happen again.
"The FCO has summoned the Iranian ambassador today to convey our strong objections."
Families of the victims of the downed Ukrainian International Airlines flight could seek compensation from the Iranian government, Downing Street indicated.
The Prime Minister's official spokesman said: "As a first step we need a comprehensive, transparent and independent investigation to know exactly what happened.
"Of course the families of the four British victims deserve justice and closure and we will continue to do everything we can to support them in getting that, including options for compensation."