NEW YORK—Russia has vetoed a U.N. Security Council resolution that would have established an international criminal tribunal to investigate the downing of a Malaysia Airlines flight last July over eastern Ukraine that killed 298 passengers.

The Security Council on Wednesday "sent the wrong message" to the families of the victims, Malaysia's Transport Minister Liow Tiong Lai told the council after the vote. "We are sending a message of impunity to the perpetrators and endangering the safety of civilian air travel over conflict zones in the future," he said.

Vitaly Churkin, Russia's U.N. ambassador, said Moscow "seeks justice" in the downing of Flight MH17, but said the resolution was politically motivated by "interested states" that acted "outside" the council in collusion with Ukraine.

Russia has introduced its own draft resolution that calls for a "transparent international investigation" that has "nothing to do with impunity" in which Russia would have more input than it has been allowed into the Dutch-led probe, yet to be completed, Mr. Churkin said. The mechanism to "try those responsible" would be considered after the Russian-proposed investigation was over, he added.

The Russian envoy said the U.S. downing of Iran Air flight 655 in 1988 by the U.S. warship Vincennes wasn't considered a crime, and that the Security Council didn't see it as a threat to international security. The U.S. paid compensation to the victims' families of the flight.

The defeated resolution on MH17 declared the incident a threat to international security, which is the legal basis for council involvement in such an issue. Mr. Churkin said there was no mention of such a threat by Western nations in the months after MH17 went down but it has "suddenly" been invoked in the resolution that Russia vetoed.

Russia also believes ad hoc U.N. criminal tribunals on former Yugoslavia and Rwanda were expensive and subject to political pressure, Mr. Churkin said. The International Criminal Court was established in 2002 to replace such courts, but there has been no move to bring the MH17 case to The Hague. Ukraine isn't a member of the ICC but could sign up to the treaty in full and approve retroactive jurisdiction.

Western diplomats have blamed Russian-back rebels in eastern Ukraine for downing the plane with a Russian-supplied surface-to air missile. The Dutch investigation hasn't yet established what weapon was used.

"Today's veto cannot and will not deny the victim's justice," U.S. Ambassador Samantha Power told the council. "While we are outraged by the outcome of this vote, no veto will stand in the way of this heinous crime being investigated and prosecuted."

Write to Joe Lauria at newseditor@wsj.com

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