Beijing said it hoped all parties would show calm, patience and flexibility so that negotiations may be resumed.
Iran has offered “serious talks” with six world powers in response to a UN demand that it stop enriching uranium,
It has until September to suspend enrichment or risk sanctions amid fears that it is building a nuclear bomb.
Tehran denies it is building a bomb and maintains it has a right to civilian nuclear technology.
The US, UK, Russia, China, France and Germany have offered Iran a package of incentives – including help with civilian nuclear technology – in exchange for suspending enrichment.
Iran’s chief nuclear negotiator, Ali Larijani, said on Tuesday that his country was ready for “serious talks” on the issue – but did not give any more details of its response to the offer.
‘Negotiated settlement’
A Chinese foreign ministry statement said Beijing was “carefully studying” Iran’s reply.
“China has always believed that seeking a peaceful resolution of the Iranian nuclear issue through diplomatic talks is the best choice and in the interests of all parties concerned,” the ministry said.
Russia echoed the Chinese stance, stressing its commitment to a negotiated solution to the crisis over Iran’s nuclear programme.
Russia will continue “seeking a political, negotiated settlement concerning Iran’s nuclear programme,” Interfax news agency quotes a Russian foreign ministry spokesman as saying.
Sanctions threat
Although Mr Larijani has spoken of “serious talks”, what the Security Council needs to know is whether Iran is willing to suspend uranium enrichment by 31 August or not, says the BBC News website’s world affairs correspondent, Paul Reynolds.
If it is not, or gives no clear response on this, the US and its allies will take it as a “no” and will press for sanctions, though these would need a separate council decision, our correspondent adds.
Iranian officials had previously said the response would address ambiguities over its right to nuclear technology.
Enriched uranium is used as fuel for nuclear reactors, but highly enriched uranium can also be used to make nuclear bombs.
Iran points out that as a signatory to the Nuclear Non-Proliferation Treaty (NPT) it is entitled to a nuclear power programme and says it has broken no rule.
But the Western powers accuse Iran of concealing an enrichment programme, and Washington has refused to rule out military action.
