China's wisdom facilitates nuclear deal: Chinese negotiator

China's wisdom played a key role in the achievement of a comprehensive agreement on Iran's nuclear program, Chinese negotiator Cheng Jingye said here on Wednesday.

After 18-month marathon negotiation, Iran and the P5+1 group, namely China, Britain, France, Russia, the United States plus Germany, reached a historic nuclear deal in the capital city of Austria.

Cheng, also the Chinese envoy to the International Atomic Energy Agency(IAEA), said in an interview with Xinhua that China played a indispensable role in the talks for the relatively balanced agreement.

In the long process of hard negotiations, China always helped overcome difficulties by presenting constructive and viable ideas and proposals, Cheng said, citing the modification of Iran's heavy water reactor as an instance.

Western states want Iran to modify its heavy water reactor to a light water reactor to address the concern of a possible technical path to a nuclear bomb through plutonium, a demand which Iran could not accept.

According to the previous design of the Arak heavy water reactor, Iran could technically produce enough plutonium for nuclear weapon, a key concern of Western countries over Iran's nuclear program.

To resolve the issue, Cheng said, China proposed to reduce the output of plutonium by technical means while keeping Iran's heavy water reactor, which is accepted by both Iran and Western states.

Chinese Foreign Minister Wang Yi said the modification of Arak heavy water reactor is one of the core issues in the nuclear negotiations, saying China play would an important role in the modification of the reactor in the future.

In the final round of the talks, Wang flied to Vienna for three times to push the talks forward.

The talks resolved many tough issues which were once seen as a mission impossible, such as capping Iran's nuclear capacity and giving greater transparency of Tehran's atomic plan.

However, Cheng did not rule out the possibility that problems might emerge during the implementation of the deal, saying no one could guarantee that there could be no changes in the future.

Cheng said the nuclear deal has dragged the West and Iran out of confrontation, and would help facilitate stability and security of the Middle East region.