U.S. National Security Adviser Tom Donilon shared Washington’s contingency plans for a possible attack on Iran with Israel’s PM, according to a senior American official, quoted by haaretz.com.The U.S. national security adviser has shared with Prime Minister Benjamin Netanyahu the United States’ contingency plans for a possible attack on Iran. According to a senior American official, National Security Advisor Tom Donilon briefed Netanyahu on the plans during Donilon’s visit to Israel two weeks ago. According to the official, who requested anonymity, Netanyahu hosted Donilon at a three-hour dinner. For part of the time, Israel’s national security adviser, Yaakov Amidror, was on hand. Donilon sought to make clear that the United States is seriously preparing for the possibility that negotiations will reach a dead end and military action will become necessary. He said reports of such preparations were not just a way to assuage Israel’s concerns.Donilon’s talks in Jerusalem were the most significant so far between American and Israeli officials here in recent weeks. Secretary of State Hillary Clinton and Deputy Secretary of State William Burns have been in Israel as well.According to the American official, Donilon shared information on U.S. weaponry and military capabilities for dealing with Iran’s nuclear facilities, including those deep underground.But another U.S. official involved in the talks with Israel said that “based on the intelligence we have, we think there is still time for diplomacy, and the time for a military operation against Iran has not yet come.”A spokesman for the U.S. National Security Council, Tommy Vietor, declined to comment on the details of a private conversation between Netanyahu and Donilon. In any case, the secretary of the U.S. Air Force, Michael Donley, told the Capitol Hill Club last week that the force’s new bunker buster bombs were ready for use if needed. In recent months, the bombs have undergone technical improvements.The bombs, each weighing 15 tons, would be intended for fortified bunkers deep underground where chemical or nuclear weapons are stored. This would include the uranium enrichment facility deep inside the mountains near the Iranian city of Qom. The United States has told Israel several times that the existence of such weapons means Iran will never reach the point where its nuclear facilities are immune to attack.