The Iranian nuclear issue cannot be resolved in just one or two discussions, a senior Chinese diplomat said on Sunday, a day after a high-level meeting aimed at addressing Tehran's nuclear plans ended in disappointment.

Two days of talks in Istanbul with the United States, France, Germany, China, Russia and Britain failed to persuade Iran to make concessions on its nuclear program, or even agree to hold further discussions.

The Iranian nuclear issue is complicated and sensitive, and obviously cannot be comprehensively resolved through one or two rounds of dialogue, Assistant Foreign Minister Wu Hailong said, according to a brief statement posted on the ministry's official website (

But still, each side needs to be dedicated to talks and negotiations in a flexible and pragmatic spirit, create mutual trust and make efforts to solve the issue comprehensively and appropriately, Wu added.

China has backed U.N. Security Council resolutions pressing Iran to abandon its disputed nuclear activities, but has close energy and trade ties with Iran and has opposed unilateral sanctions imposed by Europe and the United States.