A Dutch court on Monday adjourned the trial into the 2014 downing of Malaysia Airlines Flight MH17 until June 8 so that the defendants could have sufficient time to prepare.
The case materials consist of about 36,000 pages, according to the court in Amsterdam.
All 298 people on board Flight MH17, en route from Amsterdam to Kuala Lumpur, were killed in the downing over war-torn eastern Ukraine.
Most of the victims were Dutch.
The four suspects – Russian nationals – Igor Girkin, Sergei Dubinsky and Oleg Pulatov – and Ukrainian national – Leonid Kharchenko – are being tried in absentia.
A Dutch-led investigative team has linked them to a Buk anti-aircraft missile system believed to have been transported to the conflict area from neighbouring Russia.
The investigative team alleges that the missile system came from the Russian military and was used to shoot down the Boeing 777 jetliner over an area held by Moscow-backed rebels, with the actual intention being to down a military plane.
Girkin, a former colonel of Russia’s Federal Security Service, was the highest military commander in the rebel group in eastern Ukraine’s Donetsk region at the time of the incident, according to the investigation team.
Both Dubinsky and Pulatov were connected with Russia’s Military Intelligence Service, the investigation team has said.
The Ukrainian, Kharchenko, was in charge of a combat unit in the war-torn Ukrainian region of Donetsk, it said.
The Russian Government has adamantly denied allegations of involvement in the incident.
Russia’s Foreign Ministry has denounced the trial as having a predetermined guilty verdict.