US and Australian defence and foreign affairs ministers have discussed Russia’s response to the MH17 downing and Ukraine crisis.

Russian President Vladimir Putin’s attendance at the G20 summit in Brisbane will depend on how he responds to the Ukraine crisis in coming weeks, US Secretary of State John Kerry says.

The MH17 disaster and separatist fight in the Ukraine was discussed at the AUSMIN talks in Sydney on Tuesday, involving Mr Kerry, US Defence Secretary Chuck Hagel and their Australian counterparts Julie Bishop and David Johnston.

Mr Kerry said no decision had been made on whether Russia will be still welcome at the G20 summit in November.

“A lot of the attitudes about that issue from the various countries attending can be determined and impacted to some degree on what happens in these next days and weeks,” he told reporters.

The US understood Australia’s “deep anger and need for justice” over the shooting down of the Malaysia Airlines flight, in which 298 people were killed including 38 Australians.

“This is an unconscionable crime of a huge international order,” he said.

While a full investigation had yet to be completed, Mr Kerry said there was no doubt about the type of weapon used and where it had come from.

“We saw the take-off, we saw the hit, we saw this airplane disappear from the radar screen, so there is really no mystery,” he said.

“But we need to have the complete investigation to legitimise whatever steps are going to be taken as we go down the road.”

The world could not gloss over this because justice needed to be served, Mr Kerry said.

Russia needed to work with the Ukrainian government to provide humanitarian assistance, facilitate the MH17 investigation and ensure “those who are not Ukrainian” leave the country immediately.

The US is open to the idea of further sanctions on Russia from Australia and other nations.

“We need to be cautious and strong at the same time,” Mr Kerry said.