Ukraine's president has ordered that an combat exclusion zone of 40km be placed around the wreckage site of Malaysia Airlines flight MH17, to aid the investigation into the crash.
Petro Poroshenko says he has "immediately" ordered a cessation of hostilities within the zone "to ensure that specialists can easily work".
The search area for debris and items from the Boeing 777-200ER has been extended to 120km2 but there remains uncertainty about whether crucial equipment, particularly the flight recorders, have been transported away from the scene.
MH17 crash site
Poroshenko has accused separatist militants in the area of "elimination" of evidence and "hindering the work" of both Ukrainian and international investigators.
He has offered a presidential aircraft to transport investigators to the site, east of Donetsk. The inquiry, he adds, has started examination of the wreckage including the wing and cockpit.
Ukrainian prime minister Arseniy Yatseniuk is adamant that a surface-to-air missile attack was responsible for the crash. "At this stage we have no doubts that the aircraft was shot down."
He insists that a Buk-M1 mobile missile launcher, also known as an SA-11, was used and that such a system could not have been operated by "drunk terrorists" but by professionals with funding, weapons and training.