Jon Swaine and Phoebe Greenwood
London Telegraph 
March 5, 2012
Speaking before a critical White House showdown Monday with Benjamin Netanyahu, Israel’s prime minister, Mr Obama tried to buy more time for “crippling sanctions” against Tehran to take effect before Israel decides to strike its nuclear facilities.
“Iran’s leaders should know that I do not have a policy of containment,” Mr Obama told a major pro-Israeli conference in Washington. “I have a policy to prevent Iran from obtaining a nuclear weapon”.
Stressing that a nuclear-armed Iran also threatened American security, he added: “I will not hesitate to use force when it is necessary to defend the United States and its interests”.
However, he urged Israeli leaders to “let our increased pressure sink in”, emphasising: “Now is not the time for bluster” and citing Theodore Roosevelt’s dictum to “speak softly, but carry a big stick”.
“There is too much loose talk of war,” Mr Obama said. “Such talk has only benefited the Iranian government, by driving up the price of oil, which they depend upon to fund their nuclear programme.”