Iranian President Hassan Rouhani (C) inspects the honour guards before leaving for China at Mehrabad Airport in Tehran, Iran, on May 20, 2014. Rouhani left Tehran for Shanghai on Tuesday morning to attend the Conference on Interaction and Confidence Building Measures in Asia (CICA) summit, to be held in Shanghai on May 20-21. (Xinhua/Ahmad Halabisaz)

Iranian President Hassan Rouhani (C) smiles before leaving for China at Mehrabad Airport in Tehran, Iran, on May 20, 2014. Rouhani left Tehran for Shanghai on Tuesday morning to attend the Conference on Interaction and Confidence Building Measures in Asia (CICA) summit, to be held in Shanghai on May 20-21. (Xinhua/Ahmad Halabisaz)

Iranian President Hassan Rouhani (R) greet the head of Iranian supreme leader's office, Mohammad Mohammadi Golpayegani (L) before leaving for China at Mehrabad Airport in Tehran, Iran, on May 20, 2014. Rouhani left Tehran for Shanghai on Tuesday morning to attend the Conference on Interaction and Confidence Building Measures in Asia (CICA) summit, to be held in Shanghai on May 20-21. (Xinhua/Ahmad Halabisaz)

Iranian President Hassan Rouhani waves before leaving for China at Mehrabad Airport in Tehran, Iran, on May 20, 2014. Rouhani left Tehran for Shanghai on Tuesday morning to attend the Conference on Interaction and Confidence Building Measures in Asia (CICA) summit, to be held in Shanghai on May 20-21. (Xinhua/Ahmad Halabisaz)

Iranian President Hassan Rouhani (L) inspects the honour guards before leaving for China at Mehrabad Airport in Tehran, Iran, on May 20, 2014. Rouhani left Tehran for Shanghai on Tuesday morning to attend the Conference on Interaction and Confidence Building Measures in Asia (CICA) summit, to be held in Shanghai on May 20-21. (Xinhua/Ahmad Halabisaz)