UNITED NATIONS, Sept 26 - Limousines whisked world leaders away from the United Nations on Friday after a week of speeches, meetings and hallway diplomacy.

While they reached no breakthroughs on the world's most intractable conflicts, talks on the Iran and Ukraine wars inched forward and global powers used the venue to debate AI risks with industry leaders.

Here are the big takeaways from scores of panels, hundreds of meetings, hours spent in lines and listening to speeches – and countless cups of coffee: REBOOT OF IRAN DIPLOMACY The UN was probably most useful for facilitating the first shuttle talks between American and Iranian officials since the collapse of a ceasefire in July. Iran's Foreign Minister Abbas Araqchi and US envoys Steve Witkoff and Jared Kushner communicated through mediators.

The efforts must continue, a senior Iranian official told Reuters, even as Iranian and American leaders exchanged sharp words at the General Assembly hall, with the US threatening to "annihilate" Iran and Iran accusing the US of a "bullying mentality." The senior Iranian official said Tehran was reviewing Washington's response to its proposals, which include lifting a US naval blockade on Iranian ports and reopening the Strait of Hormuz.

The efforts must continue, a senior Iranian official told Reuters, even as Iranian and American leaders exchanged sharp words at the General Assembly hall, with the US threatening to "annihilate" Iran and Iran accusing the US of a "bullying mentality." The senior Iranian official said Tehran was reviewing Washington's response to its proposals, which include lifting a US naval blockade on Iranian ports and reopening the Strait of Hormuz.

But no agreement appeared imminent. US Secretary of State Marco Rubio cautioned that a deal would involve hard work over time.

UKRAINE GRAIN AND ENERGY Rubio also held talks with Russian Foreign Minister Sergey Lavrov, after which he said Ukraine and Russia had both voiced an interest in a limited ceasefire involving grain and energy-related targets.

Ukraine and its allies are racing to secure limited agreements on energy infrastructure and Black Sea shipping before winter, fearing renewed Russian strikes on power and heating facilities.

But hours after Rubio spoke on Wednesday, Lavrov addressed the Security Council meeting on Ukraine, showing no indication Russia was prepared to engage on any subject. "Europe, whatever it thinks, just wants to get a pause, and it wants to use it to pump the Kyiv regime with weapons," Lavrov said.

AI STEALS CLIMATE'S SPOTLIGHT Climate change — a focus of UN discussions in recent years — was largely pushed aside by debate over artificial intelligence.

The festival of diplomacy coincided with an unprecedented outpouring of concern around AI after several safety breaches, and as top researchers warned it could destroy humanity. The UN convened a Security Council meeting featuring OpenAI CEO Sam Altman, who made an appearance in person, as well as Anthropic CEO Dario Amodei. The industry leaders appealed for governments to work together to manage AI.

Underscoring the concerns, just as they spoke, Australian Prime Minister Anthony Albanese said that an AI agent developed by OpenAI infiltrated an Australian government website in June, accessing public and non-public files.

US President Donald Trump, who has dismissed AI risks as a "hoax" and "sick conspiracy," told the UN he "rejects any attempt to construct a globalist scheme to control" AI, describing it as amazing while promising the US would be careful.

SURPRISE ARRIVAL The biggest surprise arrival at the UN was Venezuela's interim President Delcy Rodriguez, who used her trip to hold first in-person talks with Trump since coming to power after US forces grabbed then-President Nicolas Maduro in a dramatic nighttime raid.

The Venezuelan delegation's focus was on restructuring its billions of dollars in sovereign debt as it met US officials, multilateral lenders and companies.

Trump used his speech to the body dedicated to global peace to declare that in Venezuela: "to the victor belong the spoils," and called an oil deal the US signed with Caracas last month "perhaps the biggest deal ever made." As Rodriguez and Trump met in New York, Venezuelan opposition leader Maria Corina Machado made three unsuccessful bids to return to her country.

SURPRISE ABSENCE The biggest surprise absence was the Sudanese army chief Abdel Fattah al-Burhan. The US withheld his visa in a move that Sudanese and other sources said was linked to a US-backed ceasefire proposal that Khartoum has resisted.

The dispute, first reported by Reuters, threatened to deepen tensions between Washington and Sudan's army at a critical moment in the civil war, which the UN calls the world's largest humanitarian crisis.

Burhan had represented Sudan at the General Assembly since the coup. Another notable absentee was Palestinian President Mahmoud Abbas, who addressed delegates by video and condemned US curbs on the Palestinian mission's access to the UN.

UNCERTAIN FUTURE The cash-strapped United Nations may no longer be in "freefall," but it remains stuck in an "open-ended crisis," International Crisis Group analyst Richard Gowan said. The organization is grappling with shrinking budgets, waning influence and mounting geopolitical conflicts.

Wars in Ukraine and Iran rage on, while Trump has denounced the 193-member body as bloated and globalist, slashed US funding and withdrawn from dozens of UN agencies.

As UN Secretary-General Antonio Guterres received a standing ovation after his final General Assembly speech, a small group of politicians and former UN officials lobbied publicly and behind closed doors to succeed him. His second five-year term ends on December 31, leaving little time for the world's major powers to agree on a replacement.

The race, conducted according to an arcane multi-step process involving "straw polls," has no clear frontrunner, but former Costa Rican Vice President Rebeca Grynspan and Guyana's UN Ambassador Carolyn Rodrigues Birkett are leading the pack.

Whoever gets the world's most difficult job will inherit an organization buffeted by crises, low morale and declining political relevancy. That person, too, will welcome the leaders to New York for next year's summit.