John Kerry told Russia it had "hours" to back off in Ukraine. That was five days ago.

Here too, the U.S. is sure that Moscow is fueling the fire in eastern Ukraine, providing heavy weaponry to rebel groups there. Russian involvement, they say, is to blame in the downing of a Ukrainian plane that killed all 49 people on board earlier this month, one of the deadliest episodes in the crisis so far. Air Force Gen. Philip M. Breedlove, the U.S. commander of NATO forces in Europe, said Monday that the weapons used by pro-Russian separatists to shoot down the military plane were likely supplied by Moscow.

So, just about everyone agrees that Putin has not done enough to de-escalate the situation in eastern Ukraine, nor is he moving at a pace they’d like. But Poroshenko seems to have more realistic expectations of Russia than Kerry did last week. “I am optimistic and I’m thinking that within a few weeks, maybe months, we can have a deal to establish peace,” he told CNN’s Christiane Amanpour on Thursday.

Reaching a potential peace deal may now be even more complicated, thanks to a different kind of deal bound to irk Putin. On Friday, Poroshenko inked a trade agreement with the European Union—the same deal one former Ukrainian President Viktor Yanukovych refused to sign in favor of closer ties to Moscow, sparking the entire crisis. Poroshenko said that the new agreement serves as a signal of Ukraine’s desire to become a member of the E.U. But a Ukraine that embraces the West is the last thing that Putin wants.