A separatist leader says the black boxes from the downed Malaysia Airlines flight MH17 have been found and brought to the eastern Ukrainian city of Donetsk.

International monitors have also viewed almost 200 bodies located in a refrigerated wagon near the crash site.

The announcement comes as Australia takes a leading role in pushing for an international investigation into the deadly Malaysia Airlines crash with Foreign Affairs Minister Julie Bishop on her way to the US.

An international outpouring of grief continues after the shooting down of flight MH17 killed 298 people, including 28 Australians and nine permanent Australian residents.

Meanwhile, Malaysia Airlines says it will retire flight code MH17 as a "mark of respect" for the 298 people killed.

Our blog captured the developments as they happened.