New York - Russia vetoed a United Nations Security Council resolution on Wednesday that sought to set up a special tribunal to try those responsible for shooting down flight MH17 over Ukraine.Eleven of the 15 members of the Security Council voted in favour of the resolution, which had been drafted by Australia, Belgium, Malaysia, The Netherlands and Ukraine.Russia exercised its veto. Angola, China and Venezuela abstained. The Council session began with a moment's silence in honour of the 298 people killed in the July 17 2014 disaster.Moscow drafted an alternative resolution that does not include a tribunal, but asks for a full international investigation and its ambassador launched into a lengthy defence of Russia's actions.Vitaly Churkin said Russian investigators had been denied equal access to the crash site and criticised what he said would have been criminal prosecution carried out "in a closed fashion"."What are the grounds to be assured of the impartiality of such an investigation?" Churkin asked in a speech to the Council, lashing out against "aggressive... propaganda in the media".Ukraine and the West have pointed their finger at pro-Russian separatists, saying they may have used a Buk surface-to-air missile supplied by Russia to down the Boeing 777 plane.Moscow denies involvement and instead accuses Ukraine's military.US ambassador Samantha Power said she was "outraged and gravely disappointed" by the vote, though no veto could shake US commitment to giving justice to families of the victims."By vetoing this resolution, Russia has tried to deny justice to the 298 victims on that plane and deny their families the chance to hold accountable those responsible," she said."It is tragic that Russia has used the privilege entrusted to it... in order to frustrate international peace and security.""The United States believes firmly that those who carried out this unspeakable crime cannot remain unnamed and unpunished," Power added."There cannot and will not be impunity for those who downed the airliner," she said.Malaysia's transport minister earlier appealed to Council members to adopt the resolution and said a tribunal would be best placed to "deliver justice to the families of the victims"."All those who travel by air will be more at risk if the perpetrators are not held to account," Liow Tiong Lai said.The flight was downed over rebel-held east Ukraine during heavy fighting between Kiev's armed forces and pro-Russian separatists.The majority of passengers on the flight from Amsterdam to Kuala Lumpur were Dutch.