MOSCOW, July 20  -- Russian President Vladimir Putin has reiterated the importance for all sides not to make hasty conclusions and politicized statements until the investigation of the Malaysian airliner crash is over, the Kremlin press service said on Sunday.

"Russia expressed its commitment and readiness to continue assisting the thorough investigation of the International Civil Aviation Organization (ICAO)," the press service said. "It is important to refrain from any hasty judgments and politicized statements until investigation is over."

Putin discussed the ongoing acute political crisis in Ukraine with British Prime Minister David Cameron late Sunday night. The two leaders stressed the necessity of a peaceful settlement as soon as possible supported by the international community.

Cameron wrote in an article published by British newspaper the Sunday Times, calling for "immediate access" to the crash site and preservation of the crime scene, adding "there must be a ceasefire. And there must be a full investigation into what happened."

The Russian President had a telephone conversation earlier with German Chancellor Angela Merkel.

The two agreed that it was important for all parties in the Ukrainian conflict to create conditions for objective and independent international investigation of the crash and guarantee the security of experts working at the site.

A Boeing 777 passenger plane of the Malaysia Airlines crashed in eastern Ukraine en route from Amsterdam to Kuala Lumpur on Thursday, killing all 298 people aboard. No proof has been found so far to clarify the cause or identify the perpetrator.