Australia says it is encouraged by UN Security Council support for an international criminal tribunal into last year's MH17 crash.

Foreign Minister Julie Bishop has returned to New York to lobby for the establishment of the tribunal.

The Malaysian Airlines plane was flying from Amsterdam to Kuala Lumpur when it crashed, killing all on board.

Many say there is evidence the plane was hit by a Russian-supplied missile fired by pro-Russian rebels.

Australia has joined other countries involved in a joint investigation of the 17 July 2014 crash, including Belgium, the Netherlands and Ukraine, to push for the tribunal and the prosecution of those responsible.

Russian opposition

Russia is expected to veto the proposal after President Vladimir Putin earlier this month said it would be "premature".

 Bishop told Australian Broadcasting Corporation (ABC) TV that despite Russia's resistance, she was encouraged by support from the UN Security Council.

"They recognise that we are seeking justice for the families of those who were killed aboard Malaysia Airlines MH17 over a year ago," she said from New York.

"We're determined to hold those responsible to account and we want to establish an independent criminal tribunal backed by the UN Security Council so that it does have international support," she said.

However, said she had requested the Russian ambassador get instructions from Moscow not to veto a resolution for the tribunal.

"This would not serve Russia's national interest, in seeking to deny the families of those aboard MH17 justice," she said, according to Australian Associated Press.

 Bishop is expected to address the council on Wednesday in New York.

A UN Security Council vote is expected some time after that.

A final report on the cause of the crash by the Dutch Safety Board is due to be released in October.