Dutch Prime Minister Mark Rutte says experts have arrived in Torez in Ukraine, where the remains of victims of the Malaysia Airlines plane crash are being stored.
The United States says there is growing evidence of Russian complicity in the downing of the plane on 17 July. Flight MH17 carrying 298 people was flying from Amsterdam to Kuala Lumpur when it was shot down by what is believed to be a surface-to-air missile over the Ukraine, killing all on board.
The three Dutch forensic scientists aim to start work on identifying 196 bodies stored in Torez on trains.
The international community is continuing to push for neutral investigators to be given full and unfettered access to the wreckage of the plane in eastern Ukraine and pressure is growing on pro-Russian rebels to allow experts to the crash site, the BBC reports.
Russia has been accused of providing the rebels with an anti-aircraft system that was allegedly used in the attack. It denies the allegations.
Mr Rutte, whose country lost 193 people, warned Russia on Monday that all political and economic options were on the table if access to the crash site remained unsatisfactory. "We want our people back," he said in parliament in The Hague.
Ukrainian Prime Minister Arseny Yatsenyuk says he is willing to cede control of the investigation to the Netherlands, while Russian President Vladimir Putin said it is essential that investigators have the security needed to carry out their work.
The Malaysian plane's flight recorders have been removed and taken to the rebel stronghold of Donetsk.
Shambolic conditions - Abbott
Australian Prime Minister Tony Abbott says his government is considering listing the shooting down the jet as an act of terrorism and criticised "shambolic" conditions at the crash site.
Mr Abbott warned Russia on Monday not to block a United Nations Security Council resolution on international efforts to investigate the attack on the plane which killed 37 Australians and two New Zealanders.
He said the the effort to recover the bodies, which are decomposing rapidly in the summer heat, looked "more like a garden clean-up than a forensic investigation".
Australia is calling for an international investigation and Mr Abbott said securing evidence at the crash site must be a priority, the ABC reports.
"Given the almost certain culpability of the Russian-backed rebels in the downing of the aircraft, having those people in control of the site is a little like leaving criminals in control of a crime scene."
Russia's ambassador to the UN is seeking changes to Australia's resolution, saying there are ambiguities in the wording. But Mr Abbot said that the world would pass swift judgement if Russia vetoes Australia's push.
"We will do our best to craft a resolution which, under the circumstances, no reasonable person could object to. And that's what we will do."
His comments came just hours after he spoke to Russian President Vladimir Putin, asking for his cooperation in the international investigation.
Australia's Foreign Minister Julie Bishop called on the pro-Russian separatists not to use bodies of those killed as pawns in their conflict with the Ukrainian government and also called for the UN resolution demanding full and unfettered access to the crash site.
Meanwhile, video footage filmed by pro-Russian rebels immediately after flight MH17 was shot down shows local rebels looking through the debris, tipping out the belongings of those on the plane. Voices are heard saying: "They're foreigners, who allowed them to fly over here?"
In the footage, which has been shown on BBC television, rebels are seen making efforts to locate the plane's black-box flight recorders and others are seen gathering up as many computer memory sticks as can be found.
Russian 'complicity'
US Secretary of State John Kerry laid out what he said was overwhelming evidence of Russian complicity in the shooting down of flight MH17, saying it was quite clear that the surface-to-air missile system used to bring the plane down had been transferred directly from Russia.
Moscow denies involvement in shooting down the airliner and has blamed the Ukrainian military. But Washington and its allies point the finger at the pro-Russian separatists who have Moscow's backing and have been accused of obstructing access to the crash sites.
Mr Kerry said the United States had seen supplies moving into Ukraine from Russia in the past month, including a 150-vehicle convoy of armoured personnel carriers, tanks and rocket launchers given to the separatists.
Britain, Germany and France have agreed they should be ready to increase sanctions on Russia over the downing of the jet when European foreign ministers meet in Brussels.
A statement from British Prime Minister David Cameron said the European Union must reconsider its approach to Russia and be ready to impose further sanctions. The leaders of the three countries also agreed to press Russian leader Vladimir Putin to ensure investigators had free access to the crash site.
'Gruesome' sight
An international observer has told of the "gruesome" sight of body bags holding the decomposing bodies of victims of the flight.
Michael Bociurkiw, a spokesperson for the Organisation for Security and Co-operation in Europe has been at the crash site during the weekend and told Radio New Zealand's Nine to Noon programme on Monday his team had visited the train station.
"At the train station it was obviously very gruesome. It's been quite warm here recently and we didn't really know what to expect but these (wagons) were actually refrigerated and that's a big contrast because ... the first time we went out to the crash sites, there were a lot of bodies lying there exposed to the elements, so now they are bagged and put in this refrigeration unit.
"But the stench was overwhelming, and one can only process or look at that with proper protective equipment."
Mr Bociurkiw's teams had visited about three of the eight intact wreckage sites and said access had improved and that there was more security, which meant they do their work without interruption. They had also visited the wreckage of the plane's cockpit and first-class section, he said.
"The impact was huge. The whole area was compressed but it was the first large area of impact where there was no apparent fire, so there are a lot of items that are recognisable, from the flight manuals of the pilots to a pilot's seat to ... mail bags, some cargo, a lot of electronics," he said.
However, it was a different story at the site of the mid-section wreckage, where the planes fuel tanks and landing gear would have been.
"That must have had a huge fireball. Everything was really and sadly incinerated, partially probably vapourised. So it was a very intense day, to say the least."