The United States said on Sunday it will make its case against Iran at the United Nations this week, insisting it wants to give diplomacy "every opportunity to succeed" in the wake of a devastating attack on a vital Saudi oil complex. Setting the stage for US President Donald Trump's address to the annual UN General Assembly on Tuesday, Secretary of State Mike Pompeo put aside threats of US military retaliation against Iran for the attack.

Washington's call for diplomacy

"President Trump and I both want to give diplomacy every opportunity to succeed," Pompeo said in an interview with ABC's "This Week".

"Our administration's taking this on in a serious way and we are working diligently to see that this has a diplomatic outcome," he said.

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"But make no mistake about it, if we are unsuccessful in that and Iran continues to strike out in this way, I am confident that President Trump will make the decisions necessary to achieve our objectives."

The United States has accused Tehran of carrying out the sneak air attacks that set aflame Saudi Arabia's Abqaiq plant and the Khurais oil field on September 14, knocking out half the kingdom's oil production. Pompeo called it "one of the largest attacks on the global energy supply in history". But despite initial warnings by Trump that US forces were "locked and loaded", the US President quickly softened his rhetoric, brushing off Republican hawks who warned that the absence of a forceful response would be read as weakness in Tehran. Trump has so far ordered stepped up sanctions against Iran and a relatively modest deployment of US troops to the Gulf, primarily focussed on defensive missions like air and missile defense. On Fox News, Pompeo said the administration was "deeply aware of the risks" of a miscalculation leading to conflagration in the tinderbox region.

"It's why we want to resolve this in a way that doesn't resort to kinetic action if it's at all possible to achieve that," he said.

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On Sunday, before leaving the White House on a trip to Texas, Trump once again left open the possibility of an unscheduled meeting on the sidelines of the UN General Assembly with Iranian President Hassan Rouhani. "Nothing is ever off the table, completely, but I have no intention of meeting with Iran and that doesn't mean it doesn't happen," Trump said. "I'm a very flexible person, but we have no intention. It's not set up." When asked if there would be any discussions between Pompeo or another American representative with the Iranian delegation at the UN General Assembly, a high-ranking American official said there was "nothing planned". But CNN's Christiane Amanpour tweeted that Iranian Foreign Minister Javad Zarif told her in an interview that Rouhani was willing to meet with Trump in New York this week "provided that President Trump is ready to do what's necessary" by exchanging sanctions relief for "permanent monitoring of Iranian nuclear facilities."

Iran denies September 14 attack

"The olive branch has always been on the table, but we're showing it again," Zarif added, according to Amanpour's tweet. The US diplomatic offensive comes as Iran has sharpened its tone with a warning from a Revolutionary Guard Corps commander that the country is "ready for any type of scenario." "Whoever wants their land to become the main battlefield, go ahead," Major General Hossein Salami told a news conference in Tehran. In a pre-recorded interview with CBS's "Face the Nation", Zarif denied Iran was behind the September 14 attack, which was claimed by Iranian-backed Huthi rebels in Yemen. "I'm not confident that we can avoid a war," he said. "I'm confident that we will not start one but I'm confident that whoever starts one will not be the one who finishes it," he said.

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Pompeo, meanwhile, defended the US strategy of applying "maximum pressure" on Iran through sanctions against criticism, saying it has resulted in Iran lashing out. He said the US sanctions campaign was just getting started. "We hope the United Nations will take a strong position. It was designed exactly for this kind of thing, where one country attacks another country and we hope the United Nations will rally around what it is."

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