It was a somber gathering, five foreign ministers to remember five of the nationality groups who died when flight PS752 was shot down in the skies over Tehran on 8 January, with the loss of 176 passengers and crew.

The Canadian foreign minister, François-Philippe Champagne, hosted the event at Canada House in central London.

He led foreign ministers from the UK, Afghanistan, Ukraine, and Sweden to light a five-wick candle in memory of those who died.

The event comes amid calls for clarity from Tehran about what exactly happened and who was responsible for the crash.

Ukrainian investigators arrived on the ground last week, but it's not yet clear how much progress the Canadian team and investigators from Boeing have made in getting to the site as they are entitled to do according to international law.

Under international law, the families of the victims are also entitled to the truth, to justice and almost certainly compensation.

In the majority of air crashes this would be a matter for the airline, but in the case of PS752 a third party, the Iranian military, is the crucial party.

Hence the political gathering in London. The delay in clarity over the tragedy from the Iranian leadership has lent an air of distrust and concern to proceedings, leaving the families of those involved in a traumatic position.

As well as the nationalities represented at Canada House, 82 Iranian citizens also lost their lives on board PS752.

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