WASHINGTON – US President Barack Obama spoke by telephone with Prime Minister Binyamin Netanyahu Monday after the latter cancelled a planned Oval Office meeting scheduled for Tuesday.During their 15-minute conversation, Obama conveyed his understanding for Netanyahu’s decision to return immediately to Israel from Canada and not stop in Washington following the deadly clash between the IDF and activists trying to break the Gaza blockade earlier in the day.RELATED:Ban Ki-moon: 'Shocked by raids'Navy escorts flotilla ships to AshdodThe two leaders also agreed to reschedule their meeting at the first opportunity. “The president expressed deep regret at the loss of life in today's incident, and concern for the wounded, many of whom are being treated in Israeli hospitals,” a statement put out by the White House read. “The president also expressed the importance of learning all the facts and circumstances around this morning's tragic events as soon as possible.”The visit had been expected to reaffirm the strong US-Israel relationship after weeks of tension and provide a public welcome to Netanyahu after his nighttime White House visit in March was conducted under a total media blackout. It was to come in the midst of nascent proximity talks between Israelis and Palestinians as the US sought to build momentum to move to direct negotiations and ahead of a high-profile visit of Palestinian Authority President Mahmoud Abbas to the White House next Tuesday.“It shows how hard it is to purposefully change the momentum” in Middle East peace-making, Jon Alterman of the Center for Strategic and International Studies noted. “Even when you try to build small steps to change things, the waves come crashing down.”He also assessed that in contrast to the Europeans, who already were using the incident Monday to reinforce calls for an end to the Gaza blockade, the Americans would want to have a fuller grasp of the situation before reviewing Gaza policy.“On the American side there’s going to be a real desire to understand what happened,” he said.