"Today we commemorate the fourth anniversary of the tragic downing of Malaysian Airlines Flight MH17, which caused the loss of so many innocent lives. For those who lost their loved ones, this day is a constant source of grief and we convey our deepest sympathy and respect to all of them," EU High Representative for Foreign Affairs and Security Policy said in a declaration on the occasion of the 4th anniversary of the downing of Malaysian Airlines Flight MH17.

Mogherini says the EU "fully supports United Nations Security Council Resolution 2166, which demands that those responsible for the downing of flight MH17 on 17 July 2014 be held to account and that all States cooperate fully with efforts to establish accountability," the EU Delegation in Ukraine has told UNIAN.

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The work of the Joint Investigation Team and the steps taken by the countries involved to come to an effective prosecution are essential in this context, according to Mogherini.

"The Joint Investigation Team on 24 May presented further findings of its independent, professional and impartial investigation, concluding that the BUK installation used to shoot down flight MH17 belonged beyond doubt to the armed forces of the Russian Federation," she said. "Against this background, we will continue to call on the Russian Federation to accept its responsibility and to fully cooperate with all efforts to establish accountability."