(CBS News) TEHRAN - Thursday was supposed to be Iran's coming out party. The 16th annual Non-Aligned Movement summit in Tehran drew the biggest gathering of international leaders ever to the Islamic Republic, since the revolution that brought the ayatollahs to power in 1979. Iran tried to put its agenda center-stage, but not all the guests stuck to Tehran's script.
Egypt's new Islamists president, Mohammed Morsi shocked the conference and his Iranian hosts with harsh criticism of Syria - Iran's number-one ally in the region. In an extended address, Morsi said he came to the Tehran summit to "announce our full and just support for a free, independent Syria that supports a transition into a democratic system and that respects the will of the Syrian people for freedom and equality."
Morsi urged the Syrian opposition to unify - in effect advocating the overthrow of President Bashar Assad - and said Egypt's "solidarity with the struggle of the Syrian people against an oppressive regime that has lost its legitimacy is an ethical duty."
Iran, a predominantly Shiite Muslim nation led entirely by Shiite Muslim clerics, is Assad's chief patron. The Syrian opposition, and certainly the armed rebel groups fighting Assad's forces on the ground, are made up almost entirely of Sunni Muslims.
Iran's president, Mahmoud Ahmadinejad, sat next to Morsi as he addressed the summit. Ahmadinejad maintained a poker face and did not respond to the remarks, which Iran's media also ignored completely.
The Syrian delegation walked out of the conference in protest.
Earlier at the summit, Syrian reconciliation minister Ali Haidar told CBS News that Iran is supportive of the Syrian government in its efforts, "combating terrorism on behalf of the entire world."
Haidar denied that Iran is providing any military support and claimed that the Syrian government is still in control of the entire country. The U.S. State Department, however, considers much of eastern Syria to now be out of the Assad regime's control, and rebel forces still have significant presence in, if not control over many neighborhoods in the key northern cities of Aleppo and Idlib.
Rebels claimed Thursday to have shot down a Syrian warplane on the outskirts of Idlib as the fighting there continues. Amateur video posted by opposition members shows the wreckage of a jet in flames, and its pilots can be seen parachuting to the ground, but there is no way to confirm what caused the plane to crash.
After Iran's supreme leader Ayatollah Ali Khamenei dismissed the United Nations as an "unjust, antiquated relic of the past" in remarks to the summit, U.N. secretary-general Ban Ki-moon took the podium later Thursday and had his own swipe at Iran.
Ban called the denial of the holocaust "outrageous." Ahmadinejad has publicly called Hitler's WWII genocide a "myth," and blamed Israel for regional terrorism. The U.N. chief also called on Iran to thoroughly comply with the International Atomic Energy Agency (IAEA) and take measures to assure the world that it is not pursuing nuclear weapons. The IAEA, the U.N.'s nuclear watchdog - has repeatedly been denied access to the Parchin military complex and other sites in question.
Ban's attendance at the NAM summit has been portrayed by Iran as public recognition that it is not an isolated nation. Secretary of State Hillary Clinton and Israeli Prime Minister Benjamin Netanyahu both asked Ban to boycott the summit.
Iran is the most sanctioned country in the world. The U.S. and the European Union have stiff financial sanctions and oil embargoes against the country as punishment for its continuing enrichment of uranium and its alleged pursuit of a nuclear weapon.
Iran's ambassador to the IAEA, Ali Soltanieh, argued in an interview with CBS News that, "the sanctions are targeting normal people, not the centrifuges." He said Iran is not importing materials for its enrichment and nuclear research, but manufacturing them in Iran, and thus the nuclear program is not impacted by the sanctions.
CBS News was restricted by Iranian authorities from conducting interviews with locals or bringing cameras into public areas to investigate Iran's claims that civilians are being unfairly hurt by the sanctions. All western reporters are under heavy restrictions and prevented from reporting outside of the conference center in Tehran.
The key speaker on Thursday was the man who really runs Iran: Ayatollah Khamenei. The ayatollah has not addressed an international audience including non-Muslims in nearly 30 years.
Unsurprisingly, Khamenei did stick to the script - not even acknowledging the conflict in Syria. He reiterated Iran's official stance on nuclear development - saying all nations have the right to produce nuclear energy, but none have the right to nuclear arms.