Updated

BEIJING -- Iran's president will attempt to shore up support from Russia and China during a closely-watched summit of Central Asian leaders beginning Wednesday in Beijing, just as concerns rise over Tehran's nuclear program.

Russia and China also are expected to discuss Syria, as they face increasingly international pressure to more forcefully respond to attacks on civilians there. The two have blocked international efforts to take a tougher stance against Damascus.

The annual meeting of leaders of the Shanghai Cooperation Organization will spotlight China's growing demand for oil and natural gas and its efforts to build stronger ties with resource-rich Central Asian nations.

China's and Russia's close economic and strategic ties to Iran will play a central part in this week's talks, with Iran looking for support as it deals with rising pressure from the US and Europe over its nuclear ambitions. Washington has expressed increasing worries that Iran is developing nuclear weapons, while Tehran insists its efforts are peaceful.

Iran, which relies on China for oil revenue and strategic support, likely will seek to mollify Beijing that it has taken steps to address international concerns. Hopes for progress were dealt a setback last month during talks in Baghdad.

China in its public statements has been calling for improved cooperation between Iran and the International Atomic Energy Agency (IAEA) even as it has dismissed US calls for tougher measures against Iran.

China "will try to persuade the Iranians to be more forthcoming and more engaged in diplomacy," according to Michal Meidan, a China analyst for Eurasia Group, adding that IAEA talks "give China room for maneuvering."

Meanwhile, Iranian President Mahmoud Ahmadinejad likely will be seeking reassurances over energy ties to Beijing. Iran is a major supplier of Chinese crude, but shipments were sharply curtailed earlier this year in what people familiar with the matter have described as a commercial dispute.

While resolved, the dispute underscores the give-and-take in China-Iran relations. "The Iranians are concerned that the Chinese are making backup plans," Meidan said.

Click here for more on this from The Wall Street Journal.