Hu meets Ahmadinejad, calls for closer ties

"As mayor of Tehran, you provided support to Chinese businesses in Iran," Hu said as he gave Ahmadinejad a warm welcome at the start of their meeting, which also included talks on the Iranian nuclear issue.

"Now that you are president, I hope that we will have many opportunities to take the relationship between China and Iran to the next level."

China and Iran have long had close economic ties, especially in the oil and gas fields, and are in negotiations over an energy deal that was tentatively inked in 2004 and could be worth more than 100 billion dollars.

As part of the initial memorandum of understanding, Sinopec, China's largest refiner, would buy 250 million tons of liquefied natural gas over 25 years, which alone could be worth more than 100 billion dollars.

However, despite a series of Chinese delegations going to Tehran, the deal has yet to be finalized.

Ahmadinejad arrived in China on Wednesday to participate in the leaders' summit of the Shanghai Cooperation Organization (SCO), a regional forum that is increasingly being seen as a counterweight to US influence in Central Asia.

The SCO groups China and Russia with the four Central Asian states of Kazakhstan, Kyrgyzstan, Tajikistan and Uzbekistan. Iran, Pakistan, India and Mongolia are observer nations.

Ahmadinejad's invitation to China for the SCO drew criticism from the United States, which accuses Iran of being the world's biggest sponsor of terrorism.

"Having Iran there as an observer... again runs counter to the idea that this is a group dedicated in part to countering terrorism in the region," State Department spokesman Sean McCormack said in Washington on Thursday.