Dutch Prime Minister Mark Rutte says he had a "very intense" phone conversation with Russian President Vladimir Putin Saturday, in which he urged the Russian leader to use his influence over Ukraine's separatists to help in the investigation of the Malaysian plane shot down over Ukraine.
Rutte said he told Putin that he must "show the world" he intends to help.
More than half of the plane's 298 passengers and crew -- all killed in the strike -- were Dutch. Rutte said he was "shocked" by images of rebels picking through victims' possessions and walking around the crash site.
Dutch Foreign Minister Frans Timmermans said Saturday people in the Netherlands are "furious" at the news of bodies being dragged around and the site being treated "improperly."
Speaking in Kyiv alongside Ukrainian President Petro Poroshenko, Timmermans said Dutch officials want to know who did this and want the proof to be there.
Poroshenko reassured officials the Ukrainian government is "doing everything possible" to allow a transparent investigation under the leadership of the International Civil Aviation Organization.
Russia, meanwhile, has denied involvement in the strike and agreed on the need for an international investigation.
In a phone call Saturday, Putin and German Chancellor Angela Merkel agreed that an independent, international commission led by the International Civil Aviation Organization should be granted quick access to the crash site.
But British Foreign Secretary Philip Hammond said international investigators were "not getting enough support" from Russia.
Hammond told reporters Saturday the Russians were not using their influence effectively enough to get the Ukrainian separatists in control of the site to allow the access needed. He said the world's eyes will be on Russia to see that the country delivers.
U.S. President Barack Obama said Friday that evidence indicates a surface-to-air-missile shot down the Malaysian plane Thursday and that it was fired from territory controlled by pro-Russian separatists.
Obama called the deaths an "outrage of unspeakable proportions" and a "wake-up call" for Europe and the world that there are consequences to an escalating conflict in eastern Ukraine.
Russia's foreign ministry said U.S. Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov agreed in a phone call Saturday that both countries will use their influence on the two sides of the Ukrainian conflict to end hostilities.
A pro-Russian separatist stands at the crash site of Malaysia Airlines flight MH17, near the settlement of Grabovo in the Donetsk region, July 18, 2014.
Pro-Russian separatists watch as Organization for Security and Cooperation in Europe (OSCE) monitors arrive at the crash site of Malaysia Airlines flight MH17, near the settlement of Grabovo in the Donetsk region, July 18, 2014.
Alexander Hug, deputy head of the OSCE mission, looks at debris at the crash site of a Malaysia Airlines jet near the village of Hrabove, eastern Ukraine, July 18, 2014.
A pro-Russian separatist looks at wreckage from the nose section of a Malaysia Airlines Boeing 777 plane which was downed near the village of Rozsypne, in the Donetsk region, July 18, 2014.
Passengers' belongings are pictured at the crash site of Malaysia Airlines flight MH17 before a visit by OSCE monitors, near the settlement of Grabovo in the Donetsk region, July 18, 2014.
Wreckage from the nose section of a Malaysian Airlines Boeing 777 plane, which was downed on July 18, is seen near the village of Rozsypne, in the Donetsk region, July 18, 2014.
Members of the media surround a relative of a passenger on board Malaysia Airlines MH17 that went down in war-torn Ukraine, at Kuala Lumpur International Airport in Sepang, Malaysia, July 18, 2014.
Ukrainian coal miners search the site of a crashed Malaysia Airlines passenger plane near the village of Rozsypne, eastern Ukraine Friday, July 18, 2014.
Candlelight prayers are prepapred for victims of the Malaysia Airlines MH17 at a church outside Kuala Lumpur, Malaysia, July 18, 2014.
Debris is pictured at the site of the Malaysia Airlines Boeing 777 plane crash, near the village of Grabovo, in the Donetsk region, July 18, 2014.
Aleksandr Borodai, Prime Minister of the self-proclaimed Donetsk People's Republic speaks at a news conference in Donetsk, eastern Ukraine, July 18, 2014.
Relatives of passengers aboard the Malaysia Airlines MH17 react as they arrive at Kuala Lumpur International Airport in Sepang, Malaysia, July 18, 2014.
A pack of cyclists, with Italy's Vincenzo Nibali, observe a minute of silence for the victims of the Malaysia Airlines Flight 17 plane crash prior to the start of the thirteenth stage of the Tour de France cycling race, Chamrousee, France, July 18, 2014.