Pro-Russian rebels take part in a military exercise near Donetsk, Ukraine, on Feb. 4. (Alexander Ermochenko/European Pressphoto Agency)

THERE’S BEEN much speculation in diplomatic circles that Vladi­mir Putin is ready to strike a deal ending the conflict he initiated in Ukraine, so as to free the stricken Russian economy from Western sanctions. Mr. Putin raised eyebrows last month by appointing two close associates to negotiate the implementation of a stalled peace settlement, including one dedicated to a new U.S.-Russia channel. However, it is not clear whether the Kremlin is genuinely ready to compromise or merely trying to split Western governments and shift blame for the diplomatic impasse to Ukraine. Mr. Putin needs to be tested, but, so far, European governments and the Obama administration are not doing what is needed to put him on the spot.

Mr. Putin’s foreign minister, Sergei Lavrov, certainly gives the impression that Moscow’s diplomatic moves are disingenuous. In a recent news conference, he claimed that the European Union had been pushed into a “trap” by the United States when it agreed that lifting the sanctions be linked to the implementation of the peace deal, known as Minsk 2. “Ukraine sits back and does nothing,” forcing the sanctions to remain in place, he charged. “Europe,” he confidently asserted, “no longer wants to be held hostage to this situation.”

In fact, Russia and the military force it controls in Ukraine’s eastern Donbass region have never respected the first step of the Minsk accord — a cease-fire. Daily skirmishes continue along the front line. Still, some European governments and business interests are ready to embrace Moscow’s narrative. They blame the government of Ukrainian President Petro Poroshenko for failing to win parliamentary approval for a constitutional amendment allowing greater autonomy for the Russian-occupied areas, and for the absence of an agreement on how to hold elections in those territories.

Mr. Poroshenko has been unable to muster the votes for the constitutional reform in the democratically elected parliament in part because of the cease-fire violations and a steady stream of Ukrainian casualties. Meanwhile, Russian-backed authorities in the occupied areas want the elections to be held on terms that would make them a sham that ratified their rule. In negotiations with State Department official Victoria Nuland, Putin aide Vladislav Surkov has shown some flexibility, prompting some U.S. officials to conclude that a deal to implement the Minsk accord is conceivable. However, it would require the assembly of a package in which Ukraine’s constitutional reform was paired with workable plans for holding elections and restoring government control over the border with Russia.

The necessary first step is an end to the shooting and other measures to ensure security, such as the deployment of international monitors to all parts of the Russian-controlled territories. Mr. Putin has shown that he could enforce a cease-fire if he chose to do so; he did so briefly in September, while Russian forces were pivoting to Syria. Rather than pressure Ukraine, the Obama administration should enlist the European Union in insisting that Mr. Putin demonstrate with acts that he is ready to end the war. If he does, the climate for a political deal could be set. If not, all will know who is to blame for a frozen conflict.