A failure of the gridlocked nuclear
Undersecretary of State Wendy Sherman said that if the talks end at their Nov. 24 deadline without a deal, "escalation will be the name of the game, on all sides."
"That is why I say the stakes are quite high here," she told an audience at the Center for Strategic and International Studies, a Washington think tank. "The alternatives are quite terrible."
Negotiators from Iran and six world powers have since January been seeking a deal that would lift international sanctions on Iran's economy if it agrees to limits on its
If no deal is reached, the Iranians could resume progress on controversial aspects of their nuclear program, such as enriching uranium to near-weapons grade. Many U.S. lawmakers have said they will immediately try to add further sanctions on Iran's economy, to seek to choke off more of the oil sales on which it depends.
Sherman hinted that the Obama administration could also turn to military action.
"Our preference is to achieve this goal by diplomatic means," she said. "But make no mistake: Our bottom line is unambiguous, crystal-clear and written in stone: Iran shall not obtain a nuclear weapon."
Despite her warnings, many observers and diplomats believe that the group will instead seek to extend the talks, to prevent the risks of just such a breakdown.
In recent weeks, Iranian, French and Russian diplomats have all floated the idea of extending the talks for months, at least, to avoid a confrontation. U.S. officials haven't publicly addressed that possibility, but they haven't ruled it out, either.
Iranian officials appear to be hoping that if talks collapse they could convince many nations that the West is to blame, and persuade them to resume buying Iranian oil and other products.
Sherman, however, insisted that if there is no deal, "the responsibility will be seen to rest with Iran."
She emphasized that the United States won't accept Iranian demands that it be allowed to keep all of its current nuclear infrastructure, including 9,400 operating centrifuges.
"Iran's leaders would very much like the world to conclude that the status quo ... should be acceptable. But obviously, it is not," she said.
She acknowledged that while the six negotiating countries -- the others are France, Germany, Britain, Russia and China -- have generally hung together, "there exist some major differences on prominent issues."