Obama, Putin Talk as Unrest Roils Eastern Ukraine

White House Tells Kremlin Diplomacy Is Still an Option Despite Escalation.

The U.S. stepped up efforts to dissuade Russia from intervening in Ukraine’s increasingly unstable east, with President Barack Obama telling President Vladimir Putin Monday that a diplomatic solution to the crisis is still possible even as he warned against further escalation.

Russia requested the call, the first between the presidents since March 28, after Mr. Putin annexed Crimea.

The White House also confirmed that Central Intelligence Agency Director John Brennan was in Kiev over the weekend, at the same time that pro-Russian separatists were taking over a string of cities and towns in eastern Ukraine.

The moves come ahead of a high-stakes meeting this week between U.S. Secretary of State John Kerry and officials from Russia, Ukraine and the European Union, as well as a visit to Kiev next week by Vice President Joe Biden.

On Tuesday, U.S. Air Force Gen. Philip Breedlove, the military commander of the North Atlantic Treaty Organization, will issue recommendations on Western military support for Ukraine. The general has privately advocated increased strategic intelligence sharing, and is expected to recommend such a step to NATO leaders.

A senior administration official said that Mr. Obama in Monday’s call made clear that a diplomatic solution is still possible, but told Mr. Putin Russia’s actions aren’t consistent with a negotiated settlement. Mr. Obama in the call also said it is up to Ukrainians, not Russia or the U.S., to decide how and whether to decentralize power to local governments.

Monday’s phone call between Messrs. Obama and Putin appeared to be more of a back-and-forth over their differences than a breakthrough discussion about a resolution.

“In answer to the concerns the American president expressed about alleged Russian intervention in the Southeast, the Russian president noted that such speculation is based on unreliable information,” a statement from the Kremlin said. It also said Mr. Putin urged Mr. Obama “to use everything the American side has at its disposal to avoid the use of force and bloodshed.”

Washington is intensifying efforts after the escalation of recent days set off alarms at the White House.

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