"The Ukrainian government, on my orders, is doing all that is possible to investigate this terrorist act. The investigation will be conducted under the auspices of the International Civilian Aviation Organization and will be done as clearly as possible," Petro Poroshenko said.

On Saturday, Russian Foreign Minister Sergei Lavrov and US Secretary of State John Kerry agreed on the need for an absolutely unbiased, independent and open international investigation. The diplomats also agreed all evidence should be made available for examination. Malaysia has sent a 131-member delegation to Ukraine. 

Its transport minister flew to Kiev on Saturday evening to ensure the delegation gets safe access to the crash site. The Organization for Security and Co-operation in Europe team reached the crash site on Saturday for the second time. Its spokesperson said the monitors were not at the site to investigate but to "observe and collect the facts." Germany says it will send two experts to support the probe. 

The location of the black boxes remains a mystery. The separatist leadership insists it has not located them. The OSCE mission also says it has received no information on the boxes’ whereabouts. The Malaysia Airlines Boeing 777 plane crashed Thursday in eastern Ukraine near the Russian border. All 298 people on board were killed.