President Obama has signaled Iran that the United States would accept an Iranian civilian nuclear program if Supreme Leader Ali Khamenei can back up his recent public claim that his nation “will never pursue nuclear weapons.”…

Obama advised Erdogan that the Iranians should realize that time is running out for a peaceful settlement and that Tehran should take advantage of the current window for negotiations. Obama didn’t specify whether Iran would be allowed to enrich uranium domestically as part of the civilian program the United States would endorse. That delicate issue evidently would be left for the negotiations that are supposed to start April 13, at a venue yet to be decided…

The challenge for negotiators is whether it’s possible to turn Khamenei’s public rhetoric into a serious and verifiable commitment not to build a bomb. When Obama cited this statement to Erdogan as something to build on, the Turkish leader is said to have nodded in agreement.