Investigators probing the downing of a Malaysia Airlines jet in eastern Ukraine in which 298 people died in 2014 are expected to name suspects.
The Dutch-led Joint Investigation Team (JIT) will present new evidence and announce charges for the first time.
Relatives of those killed on the plane said they had been told that four men would be charged with murder.
Passenger flight MH17 was en route from Amsterdam to Kuala Lumpur when it was shot down over conflict-hit Ukraine.
Investigators blame Russian-backed separatists who they say targeted the plane with a Russian-made missile.
