Prosecutors conducting the criminal investigation into the downing of flight MH17 over eastern Ukraine two years ago said on Friday it was at "a very advanced stage" and that they would present their conclusions after the summer.
In a statement, prosecutors said they had made "several requests" for legal assistance from countries involved in the case, but were still waiting for information from Russia about the Buk missile that is believed to have brought down the Malaysian airliner, killing 298 people.
They said the final report would detail the nature of the weapon used and the exact location from which it was fired. The airliner crashed in territory held by Moscow-backed rebels against the Kiev government.
Two thirds of the airliner's passengers were Dutch. The disaster prompted Europe and the United States to level sanctions against Russia and brought east-west tensions to their highest pitch in decades.
The investigators, from the Netherlands, Australia, Malaysia, Belgium and Ukraine, said they would present their conclusions to a court or criminal tribunal. Their governments have pledged to bring the perpetrators to justice, if necessary by setting up an international tribunal.
Russia cast its Security Council veto to block a motion to set up a United Nations-backed tribunal to try the case.