US Secretary of State John Kerry and Chinese Foreign Minister Wang Yi agreed Thursday on the need for a positive response by Iran in renewed nuclear talks, a US official said.
"Both the US and China believe that Iran should cooperate and should respond positively to the offer on the table," the official told reporters.
Kerry later Thursday will hold one of the highest-level meetings between Iran and the US since the 1979 revolution when he sits down with his Iranian counterpart Mohammad Javad Zarif for nuclear talks led by the five permanent members of the UN Security Council and Germany.
The group, dubbed the P5+1, made a new offer to Iran earlier this year, before Rouhani's election, on how to overcome a current stalemate in the nuclear dossier.
It is believed to have offered an easing of international sanctions which have crippled the Iranian economy, in return for a slow down of Iran's controversial uranium enrichment program.
But the Iranian government has yet to respond fully to the offer.
Kerry and Wang met just hours before the landmark meeting of the global powers seeking to rein in Iran's suspect nuclear program.
"On Iran they were coordinating in the run-up to today's P5+1 meeting," the senior State Department official said.
"They talked through the elements of the diplomatic track as well as the sanctions track."
Kerry also asked Wang to share his impressions of the new Iranian leadership which took power in August, after recent Iranian-Chinese talks on the sidelines of a conference in Bishkek.
"The foreign minister shared a bit of his thinking with regard to the new leadership in Iran," the US official said, but refused to go into further detail.
New Iranian President Hassan Rouhani, seen as a moderate in Iranian politics, has made overtures to the West since taking office.