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MOSCOW, July 18 (Reuters) - Pro-Russian separatists in Ukraine have agreed to provide assistance in an investigation into the downing of a Malaysian passenger airliner and will ensure safe access for international experts visiting the site, the OSCE said on Friday.
The Organization for Security and Cooperation in Europe (OSCE), a security and rights body, said in a statement on its website that a "contact group" of senior representatives from Ukraine, Russia and the OSCE had held a video conference with the separatists, who pledged to cooperate with Ukrainian authorities in the investigation.
Kiev had complained that the separatists prevented Ukrainian officials from reaching the site of the crash, in which all 298 people on board were killed. The separatists were later quoted as saying they had found one of the black box flight recorders.
"As a matter of priority, they (the separatists) shall close off the site of the catastrophe and allow local authorities to start preparations for the recovery of bodies," the OSCE said.
It said the rebels had committed to providing safe access and security guarantees to the national investigation commission, including international investigators, in the area under their control.
The plane came down on Thursday near Ukraine's border with Russia, close to the regional capital of Donetsk in astern Ukraine, where the separatists rose up against central rule from Kiev in April.
A separatist leader said the talks with Kiev over the investigation were expected to continue on Friday, adding that a three- to four-days ceasefire was being discussed to facilitate the investigation.
Ukraine and Russia traded accusations of blame over the incident. The United States has noted that it took place against a backdrop of Russian support for Ukraine rebels. Moscow denies backing the rebels militarily. (Reporting by Vladimir Soldatkin; Editing by Timothy Heritage)