WATCH: Donald Trump, Hassan Rouhani and Antonio Guterres speak at UNGA

It's the opening day of the United Nations General Assembly debate in New York and US President Donald Trump and Iranian leader Hassan Rouhani are taking to the podium. The morning session started at 9am (Coordinated Universal Time-5), and runs until 2.45pm. The UN Secretary General, Antonio Guterres, presented a report, announcing a new summit on climate change next September. Then President of the General Assembly, Maria Fernanda Espinosa Garces, laid out her priorities for the session. Brazil made the first speech among the individual nations, which traditionally would be followed by the host nation, the United States, but Mr Trump had not arrived in time. The Ecuadorian president spoke instead. Later in the morning session, Iran's President Rouhani will address the assembly. Mr Trump and Mr Rouhani's appearances at the UNGA come four months after the US ditched a nuclear deal with Tehran. Hours before taking to the podium, Mr Trump tweeted that he did not have any plans to meet with Mr Rouhani, but says he remains open to the idea. In his address, Mr Rouhani will stress that Iran continues to stick to the 2015 deal and will likely portray the US as a pariah for breaking its international commitments. ________________ ________________ The current US administration "seems determined to render all international institutions ineffectual," Iranian President Hassan Rouhani told the General Assembly, criticising the US for backing out on the nuclear deal. Mr Rouhani promised to match violation for violation, threats for threats and step for step. In a rebuke to US President Donald Trump, who spoke just hours before, Mr Rouhani said Iran was pleased other countries did not "acquiesce" to the US demands to break the deal. Read the full story here ________________ French President Emmanuel Macron launched a passionate defence of multilateralism and defended a diplomatic end to conflict between Israel and Palestine. "What can resolve the crisis between Israel and Palestine? Not unilateral initiatives, nor trampling on the legitimate rights of the Palestinian people to legitimate peace," Mr Macron said in what is seen as a rebuke to Mr Trump. "There is no credible alternative to the two-state solution." Mr Macron also launched a strong defence of multilateralism, calling for a new world order based on regional blocs. ________________ Turkey cannot remain silent over the use of sanctions as "weapons," the country's president, Recep Tayyip Erdogan told the UN General Assembly. Rebuking the US for the doubling of tariffs on Turkish aluminium and steel imported into the US. "None of us can remain silent to the arbitrary cancellation of commercial agreements and the use of economic sanctions as weapons," Mr Erdogan said his country's address in the General Debate. "We are in favour of solving our problems through conducting a constructive dialogue on equal terms," he said. The US and Turkey are at odds over interests in Syria and are in a bitter standoff over the fate of an American evangelical Christian pastor. ________________ At the opening of the 73rd session of the United Nations General Assembly, US President Donald Trump set a combative tone against Iran, calling on the international community to isolate the regime. Mr Trump said "many countries in the region strong supported my decision to remove the United States from the Iran deal." He also asked, "all nations to isolate Iran's regime as long as it continues." Read our full coverage of Mr Trump's speech here ________________ In an unexpected turn of events, Mr Trump will not speak second as he had not arrived by the time Brazil had finished speaking. Lenin Moreno of Ecuador took to the stage instead. Mr Trump arrived shortly afterwards and is due to speak later. Traditionally, as the host nation, the United States speaks second. ________________ UN General Secretary Antonio Guterres kicks off the general debate saying that multilateralism is under threat and “under fire precisely when we need it most”. In his speech to the general assembly, he harked back to Europe a century ago during WW1 and the emergence of a unity of nations to address global war. He also made references to war in Syria and Yemen, the Rohingya crisis and the transfer of refugee status for the Palestinian people. He called upon the member states to band together to avoid the humanitarian toll in those countries and to help remedy the violence that has taken place. ________________ Read more: Donald Trump and Hassan Rouhani set for UN clash How is the order of speakers at the UN General Assembly decided? The most memorable moments of the UN General Assembly ________________

WATCH: Donald Trump, Hassan Rouhani and Antonio Guterres speak at UNGA

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