WASHINGTON -- President Obama pledged to try through any means possible to engage Iran in negotiations over its disputed nuclear program, saying he wouldn’t be “constrained by diplomatic niceties and protocols.”

Obama, appearing at his first White House news conference since winning reelection last week, said reports that the United States and Iran have agreed to one-on-one talks are false, but said he intends to try again to open a dialogue between Iran and the six world powers that have tried to negotiate an end to the stand-off.

“I think there is still a window of time for us to resolve this diplomatically,” Obama said.

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He repeated the commitment he made during the presidential campaign that he would not allow Iran to obtain a nuclear weapon.

Diplomats and outside experts have said they expect the United States and Iran to begin reengaging in the next few weeks. A resolution has become more urgent because Israel’s government, which has threatened to bomb Iran to destroy its nuclear infrastructure, has warned that it may be too late to stop Iran from being able to build a nuclear weapon by next summer.

Iran’s economy has been battered by stiff U.S. and European economic sanctions, including an oil embargo. But Iran offered few concessions on its nuclear program during three rounds of talks last spring. And while key Iranian officials have indicated a desire for more talks, deep divisions remain among them on the wisdom of compromise with the West.

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paul.richter@latimes.com

