Malaysia plans to send investigators to the crash site of MH17 in Ukraine to retrieve body parts still scattered across fields.

"We intend to send our teams to the crash site as soon as possible," Malaysian Prime Minister Najib Razak said Saturday in the capital of Kuala Lumpur.

Malaysia will work closely with Australia, Ukraine and the Netherlands to ensure that the remains are returned to their families, he said.

Malaysia Airlines Flight 17 was headed from Amsterdam, Netherlands, to Kuala Lumpur when it was shot down over eastern Ukraine on July 17.

Australian Prime Minister Tony Abbott, who was in Kuala Lumpur for a bilateral meeting with Najib, reiterated the need for an international investigation.

"We owe it to the families of the victims ... not to rest until the perpetrators of this atrocity are brought to justice," Abbott said.

"It's quite likely that there are remains still left strewn across the fields of eastern Ukraine," he said.

Dutch investigators plan to issue a preliminary report Tuesday on the crash. Of the 298 people killed, around two-thirds were from the Netherlands.

More investigations will be conducted before a final report is issued, the Dutch Safety Board has said. The final report is expected within a year after the crash.

It's unclear who downed the plane, but the United States and Ukraine have accused pro-Russian separatists operating in the region of hitting it with a missile.

After the crash, the separatists took control of the site for weeks, combing through the wreckage and hindering access to investigators.

The rebels in the region signed a ceasefire agreement with Ukraine's government Friday after past attempts to stop the conflict failed.

(CNN)