China says placing sanctions on Iran is not the right way to resolve the controversy over its nuclear plans.
Foreign Ministry spokeswoman Jiang Yu called on all sides to "redouble diplomatic efforts" to persuade Iran to ends its nuclear programme.
Her remarks came after Russia indicated it could soften its longstanding opposition to further sanctions.
Iran's nuclear ambitions are set to lead Thursday's nuclear proliferation debate at the UN General Assembly.
Tehran says its nuclear programme is for civilian use only but many Western states believe it is seeking to develop nuclear weapons.
Speaking in Beijing, Ms Jiang said: "We believe that sanctions and exerting pressure are not the way to solve problems and are not conducive for the current diplomatic efforts on the Iran nuclear issue."
Correspondents says Iran's oil and gas industries are likely to be affected if sanctions are strengthened, which could explain China's reluctance to back further restrictions.
Wide focus
Russia has already agreed to limited sanctions on Iran but has so far opposed any additions.read more
