Oil started the week with a risk premium, gapping higher, but has since subsided lower. This alert would seem to add to the sense that Washington is preparing for the possibility of escalation, but warnings of this kind have been issued repeatedly and are not a decision in themselves. The clearer price driver is the binary choice Trump has described between military action, continued economic pressure or a deal, which puts the UN General Assembly week at the center of oil and gas risk. A credible move toward talks would ease the premium, while any strike or new attack on Gulf infrastructure would extend it. The mention of airspace closures is worth watching for regional aviation and shipping, which feed into fuel demand and freight costs.---Washington has told Americans to get out of Iran while Trump weighs Tehran's terms for ending the war, and the answer he gives at the UN this week will set the tone for oil.Summary:The US Virtual Embassy in Iran issued a security alert telling Americans not to travel to Iran for any reason and those inside to leave now, warning of possible flight cancellations, airspace closures and other travel disruption.The alert follows a separate State Department notice on Saturday advising Americans in the Middle East to exercise heightened vigilance and prepare for possible travel disruption after new Houthi attacks on Saudi Arabia.Iran said on Saturday it sent conditions to Washington through Qatar for ending the war, including an end to fighting on all fronts, the release of frozen funds and an end to the US naval blockade, and it is awaiting Trump's response.Trump returned early from Camp David on Saturday and has said he is in a "deciding mode" on military action, continued economic pressure or a deal. He also told Fox News that very big things could happen soon.US Central Command said it has redirected more than 100 vessels as it tightened the blockade of Iranian ports.Trump is due at the UN General Assembly this week, where he plans to make the case that Iran cannot obtain a nuclear weapon, according to US Ambassador Mike Waltz.The US Virtual Embassy in Iran has urged American citizens to leave the country immediately, warning of potential flight cancellations, airspace closures and other travel disruption amid rising tensions across the Middle East. The alert, reported by ANI and Fox News, tells Americans not to travel to Iran for any reason and says citizens inside the country should leave now. Washington has no diplomatic or consular presence in Iran, and Swiss diplomats act as its protecting power there.The warning comes as President Donald Trump weighs how to respond to conditions Iran says it has sent through Qatari mediators for ending the war. Mohsen Rezaei, secretary of Iran's Supreme National Security Council, said the terms include an end to the fighting on all fronts, the release of frozen Iranian funds and an end to the US naval blockade, and that Tehran is awaiting Trump's response. Fox News reported that Iran set out seven core demands. Trump returned to the White House on Saturday evening, earlier than planned, after leaving Camp David. He has described himself as being in a deciding mode, weighing military action, continued economic pressure or a deal, and told Fox News on Sunday that very big things could happen soon.Military pressure is continuing in parallel. US Central Command said its naval forces have redirected more than 100 vessels as they tighten the blockade of Iranian ports. On Saturday, the State Department separately advised Americans in the Middle East to exercise heightened vigilance and prepare for possible travel disruption, after new attacks by Iran-backed Houthi forces on Saudi Arabia, including a ballistic missile aimed at Riyadh that Saudi forces intercepted. Iran's Foreign Minister Abbas Araqchi has left for New York to attend the UN General Assembly, and Turkey has said it is working with other countries on new proposals to bring the United States and Iran toward an agreement.Trump is due at the UN this week, and Waltz said he plans to use the address to argue that Iran must be prevented from obtaining a nuclear weapon. President Xi Jinping's visit to Washington on Thursday adds to a crowded diplomatic calendar.The Virtual Embassy has urged Americans to leave Iran several times this year, including during the January unrest and ahead of talks in Oman in February, so the wording alone is not a reliable signal that action is imminent. What is different is the timing, since it coincides with an unanswered Iranian offer, the tightened blockade and Houthi attacks on Saudi Arabia. The mention of airspace closures is the detail worth watching.Attention now turns to Trump's response to Iran's conditions, his UN address, and whether talks through Qatar or Turkey gain traction. Any strike, or fresh attacks on Gulf energy infrastructure, would raise the risk of further supply disruption, while a step toward a deal would ease it. This article was written by Eamonn Sheridan at investinglive.com.