President Obama added a brief statement to his schedule this morning to come to the podium and ask Russian separatists in Ukraine what they’re trying to hide at the MH17 crash site.

State Department spokeswoman Jen Psaki said Saturday that OSCE monitors were only allowed 75 minutes at the crash site Friday and fewer than three hours on Saturday, all confined to a small area. “The site is not secure, and there are multiple reports of bodies being removed, parts of the plane and other debris being hauled away, and potential evidence tampered with. This is unacceptable and an affront to all those who lost loved ones and to the dignity the victims deserve,” Psaki said.

The location of the black boxes was also uncertain, with rumors over the weekend saying that the rebels turned the flight recorders over to Moscow.

“Now, international investigators are on the ground. They have been organized. I’ve sent teams. Other countries have sent teams. They are prepared. They are organized to conduct what should be the kinds of protocols and scouring and collecting of evidence that should follow any international incident like this,” Obama said on the South Lawn of the White House.

“And what they need right now is immediate and full access to the crash site. They need to be able to conduct a prompt and full and unimpeded, as well as transparent investigation. And recovery personnel have to do the solemn and sacred work of recovering the remains of those who were lost,” he added.

Ukrainian President Petro Poroshenko has declared a demilitarized zone around the crash site, but the separatists are still hampering the investigation.

“As investigators approached, they fired their weapons in to the air. The separatists are removing evidence from the crash site. All of which begs the question: What exactly are they trying to hide?” Obama said. “Moreover, these Russian-backed separatists are removing bodies from the crash site, oftentimes without the care that we would normally expect from a tragedy like this. This is an insult to those who’ve lost loved ones. This is the kind of behavior that has no place in the community of nations.”

The president said that given Russia’s “extraordinary influence” over the separatists, Russian President Vladimir Putin should have greater pull in getting them to behave.

“President Putin says that he supports a full and fair investigation, and I appreciate those words, but they have to be supported by actions,” Obama said. “The burden now is on Russia to insist that the separatists stop tampering with the evidence, grant investigators who are already on the ground immediate, full and unimpeded access to the crash site.”

“If Russia continues to violate Ukraine’s sovereignty and to back these separatists, and these separatists become more and more dangerous and now are risks, not simply to the people inside of Ukraine but the broader international community, and Russia will only further isolate itself from the international community, and the costs for Russia’s behavior will only continue to increase,” he added.

Putin made his own address earlier today, insisting “no one should and no one has the right to use this tragedy to pursue their own political goals.”

“I believe that if military operations had not resumed in eastern Ukraine on June 28, this tragedy probably could have been avoided,” Putin said. “…All those who are responsible for the situation in the region must take greater responsibility before their own peoples and before the peoples of the countries whose citizens were killed in this disaster.”

Poroshenko told CNN this morning that he doesn’t see “any differences from the tragedy of 9/11″ and the shooting down of the civilian airliner.

“We should demonstrate the same way of reaction,” said the Ukrainian leader.