Censor.NET reports referring to Poroshenko's Facebook page.
"Today, lighting the candles of memory, we bow our heads before the 298 innocent victims of MH17 flight. A terrible tragedy, an unspeakable pain that sounded in the hearts of families and friends, in each of us. Then and now.
"A daring crime that would not have happened, if not for Russia's aggression, Russia's anti-aircraft system and missile brought from the territory of the Russian Federation.
Read more: Russia closed its border airspace right before MH17 crash, - Forbes
"Our responsibility to the dead and the future generations is to show the terrorist-aggressor that responsibility for all committed crimes is inevitable.
"That's why, without a second's hesitation, in the first days after the tragedy, I decided to allow the Netherlands to investigate the crime. Without any hesitation, within the scope of my authority, a few days ago, we signed an agreement between Ukraine and the Netherlands introducing a mechanism for bringing the perpetrators of this crime to justice.
"This is our common response to the geopolitical ambitions of those who seek to derail the establishment of truth at the highest international level.
"I am convinced that the impartiality of the Dutch justice will help complete this quest.
"This is our common duty in the memory of those whose heart beats were stopped by a Russian missile exactly three years ago," said the president.
Malaysia Airlines Boeing 777, flying from Amsterdam to Kuala Lumpur, was shot down over the Donetsk region on July 17, 2014. 298 people died in the crash. The passengers were citizens of 10 countries. The majority of victims (196) were Dutch nationals.
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