After months of intense negotiations, global powers and Iran launched into a key weekend of talks Saturday amid signs they may be within sight of a historic nuclear deal to end a 13 year standoff. While all sides remain cautious, Iranian Foreign Minister Javad Zarif said the world had “never been closer” to reaching an unprecedented accord with his country aimed at blocking Iran’s pathways to developing nuclear arms. In signs of a possible breakthrough on one of the thorniest issues still blocking a deal, the IAEA announced Saturday that it may be able to complete a probe into wether Iran has ever sought nuclear weapons by the end of the year. In a rare move, Zarif also offered the promise of greater cooperation to tackle other global problems, such as the rise of the Islamic State group, should the deal be sealed. Speaking in English, Zarif said in a YouTube message that at “this eleventh hour despite some differences that remain, we have never been closer to a lasting outcome.” “Getting to yes requires the courage to compromise, the self confidence to be flexible, the maturity to be reasonable,” he said. But he added that Iran was ready to strike “a balanced and good deal” which could open new horizons to address important common challenges.” “Our common threat today is the growing menace of violent extremism and outright barbarism,” he said in reference to IS. After missing several deadlines, the so-called P5+1 group- Britain, China, France, Germany, Russia and the United States- have now given themselves until Tuesday to complete the deal.