At a joint press conference, Kerry spoke about the ongoing crisis in Ukraine, the investigation of downed Malaysia Airlines Flight 17, and the role Russia is called to play in both.
Tuesday's meeting comes 10 days after MH17 crashed in Ukraine's restive east, in an area controlled by Russian-backed separatists.
Kerry lamented that in those 10 days, despite the deployment of a team of international investigators, "investigators still have not received full, unfettered access to the crash site."
It is "absolutely necessary," he said, for the separatists to step away and allow the investigation to move forward. And Russia must use its influence over the separatists, who look to Russia for funds and weapons, to encourage their cooperation.
"Beyond the crash site, fighting continues" in a crisis Kerry said "has gone on too long."
The Ukrainians have expressed a readiness to accept a cease-fire immediately, recognizing, he said, "it is the only way this crisis is going to come to an end."
Yet there is "clear evidence" that Russia continues to provide arms and funds across the border to Ukrainian separatists.
Despite Russian Foreign Minister Sergey Lavrov's agreement Monday to "specific proposals" to de-escalate the crisis, Kerry lamented that Russian actions fail to demonstrate "legitimate desire."
Again, Kerry underlined, "President Putin can make a huge difference if he chooses to."
If Russia fails to act, Kerry cautioned the U.S. is prepared to impose further sanctions.