Russia said Saturday it supports a transparent international investigation of the downing of a Malaysian airliner, but U.S. and other Western officials said they saw no evidence Moscow was seeking to impose that message on its eastern Ukrainian allies who still control the site of the crash.

“It’s another case of the Russians saying one thing and doing another,” a senior Obama administration official said. “They say they want to abide by an international investigation, but there’s more that they can do in terms of calling on the separatists to give unfettered access” to investigators still barred from the debris field.

In a telephone conversation with Russian Foreign Minister Sergei Lavrov, Secretary of State John F. Kerry “underscored that the United States remains deeply concerned” that international investigators were denied access, and that victims and debris were reportedly being “tampered with or inappropriately removed from the site,” a State Department statement said.

A Russian statement said Lavrov and Kerry “agreed that all physical evidence, including the black boxes, must be made available for such an international investigation and that, on the ground, all necessary arrangements must be made for access by an international expert team.”

Although the Russians said that the United Nations’ International Civil Aviation Organization should lead the investigation, Lavrov also “stressed the importance” of including the Interstate Aviation Committee, the Moscow-based civil aviation authority established in 1991 with 11 states of the former Soviet Union, including Ukraine.

The committee’s participation would give Russia access to the investigation, although no Russian citizens were among the 298 aboard the flight. A second Obama administration official said that there was no reason to exclude Russia from what is intended to be a completely open inquiry. Officials spoke on the condition of anonymity to expand on publicly released statements.

Dutch Prime Minister Mark Rutte said that he had called on Russian President Vladi­mir Putin to “take responsibility” for the situation when the two spoke by telephone Saturday. Putin “has to show that he will do what is expected of him and will exert his influence,” Rutte told a news conference.

Putin also spoke Saturday with German Chancellor Angela Merkel, who “once again” asked him “to exercise his influence over the separatists” to reach a cease-fire and begin political negotiations over the wider Ukrainian conflict, a German government statement said.

After calls with Rutte and Australian Prime Minister Tony Abbott, the office of British Prime Minister David Cameron said that “all three leaders are clear that President Putin needs to actively engage with the international community and use his influence on the separatists to ensure they allow access to the crash site.” There were 27 Australian citizens aboard the flight.

There is no precedent for the scale and circumstances of the proposed international investigation, and it remains unclear how the probe will be organized once access is obtained. The Netherlands, Britain and others have already sent large teams to Kiev, where representatives of the U.S. National Transportation Safety Board and the FBI have also arrived. Malaysia, which lost 44 citizens, is also expected to send a team.

While most attention Saturday focused on growing outrage over the delay in the investigation, Cameron’s statement also said he and Rutte agreed that the European Union “will need to reconsider its approach to Russia in light of evidence that pro-Russian separatists brought down the plane.”

Europe, which has far more extensive economic ties with Russia, has been reluctant to go as far as the United States in imposing economic sanctions against the Russians for aiding the separatists. The administration has indicated it expects the Europeans will be more willing to punish Russia if it is proved to be even indirectly responsible for the shooting down of the plane.

Aviation history is littered with civilian planes that were shot from the sky, intentionally or not, by military weapons. Malaysia Flight 17 was cruising at 33,000 feet, more than half a mile higher than Mt. Everest, when a missile hit it July 17. And the missile’s range is believed to be more than twice that high.

In public statements by President Obama and other senior officials Friday, the administration did not directly accuse the separatists. Instead, it said that the plane was downed by a surface-to-air missile fired from separatist-held territory and noted that Russia has supplied the separatists with heavy weaponry, including surface-to-air missiles.

Much of the Kerry-Lavrov conversation centered on repeatedly failed efforts to impose a cease-fire in eastern Ukraine. Kerry, the statement said, “urged Russia to take immediate and clear actions to reduce tensions in Ukraine; to call on pro-Russian separatists . . . to lay down arms, release all hostages and engage in a political dialogue . . . to halt the flow of weapons and fighters into eastern Ukraine” and to allow international monitors to help secure the border.