Putin will also have a meeting with Iran's Supreme Leader Ayatollah Ali Khamenei.
It was noted that the tripartite cooperation between Azerbaijan, Iran and Russian Federation has great potential, and this format can yield a good result for cooperation in important areas.
He will finally take part in a trilateral meeting with Rouhani and Azeri President Ilham Aliyev, who has earlier arrived in the Iranian capital.
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Police said Saipov didn't obey orders to drop the weapons and Nash opened fire, hitting him in the abdomen. Nash was treated at a hospital for ringing in his ears but was otherwise unhurt, ABC News reported .
It is pertinent to mention that Chief of Russian armed forces Gen. Valery Gerasimov held meeting Iranian Chief of forces Gen. Mohammad Hossein Bagheri in Tehran before Tripartite Summit started. Putin and his Iranian hosts are expected to discuss the nuclear deal and regional crises such as the Syrian conflict, in which Moscow and Tehran are the main backers of President Bashar al-Assad, while Washington, Turkey and most Arab states support opposition groups seeking to overthrow him.
"The role of Russian Federation in the direction of consolidation and sustainability of the Joint Comprehensive Plan of Action (JCPOA) and fulfilment of its obligations by all negotiating parties is also important", said the President, stressing that the JCPOA is multilateral agreement and its preservation is very important for regional and worldwide peace and stability". "Western diplomats hope that Russia would neutralise its tilt towards Tehran after this high profile Russia-Saudi Arabia contact", reports Eurasia News.
Issue of economic cooperation was also discussed during the meeting.