German Chancellor Angela Merkel and Russian President Vladimir Putin have agreed upon an international investigation into the downing of a Malaysian Airlines plane over Ukraine, Berlin said on Saturday.

The two leaders, who spoke on the telephone, "agreed that an international, independent commission under the direction of the United Nation's International Civil Aviation Organization should quickly have access to the site of the accident ... to shed light on the circumstances of the crash and move the victims," a German government statement said.

A Kremlin statement on the same phone call said "both sides stressed the importance of a thorough and objective investigation of all circumstances relating to what has happened" and said Merkel gave a "positive assessment of Russia's readiness to send its representative to participate in the investigation."

The two leaders also agreed that a contact group comprising Ukraine, Russia and the Organization for Security and Cooperation in Europe should meet "quickly" with the aim of reaching a ceasefire in the conflict between Kiev and the rebels in eastern Ukraine, the German government statement said.

"The chancellor once again asked President Putin to exercise his influence over the separatists in order to reach this objective," it said.

However, the Kremlin statement said the contact group should include separatist representatives, a move opposed by Kiev.

World leaders have called for a rapid investigation into the accident that killed nearly 300 people on Thursday.

President Xi Jinping on Friday sent condolences to Malaysia and the Netherlands over the loss of lives.

In a message of condolences to Malaysian Supreme Head of State Abdul Halim Mu'adzam Shah, Xi said he was shocked to learn about the crash.

"On behalf of the Chinese government and people, I express deep sympathy to your country over the unfortunate event and convey profound condolences to all the deceased, including those from your country, on board," Xi said.

In another message, Xi told Dutch King Willem-Alexander he was shocked to learn about the crash that killed a large number of Dutch passengers.

"We empathize with the Dutch government and people over grief. I, myself, and on behalf of the Chinese government and people, express deep sympathy to you and convey profound condolences to the deceased from your country," Xi said.

Afp - Reuters - Xinhua