China urged other governments to stay cool-headed in their handling of the Iranian nuclear dispute as Beijing dispatched an envoy to Tehran to discuss the issue.

Assistant Foreign Minister Cui Tiankai was scheduled to arrive in Iran on Friday. He is to go later to Russia.

"We hope all parties will adopt a cool-headed approach," Chinese Vice Foreign Minister Yang Jiechi said at a news conference. "Dialogue is better than confrontation. We should work together toward this end."

Yang was responding to a question about whether Chinese President Hu Jintao would raise the Iranian and North Korean nuclear issues in talks with U.S. President George W. Bush to be held in Washington.

Yang said the leaders would talk about international issues of common concern.

"Obviously the question of non-proliferation is an important subject," he said.

Iran says its uranium enrichment is for power-generating purposes, while the West says it is intended for nuclear weapons.

The U.N. Security Council has given Iran until April 28 to cease enrichment of uranium. Iran has rejected the demand and announced Tuesday that, for the first time, it had enriched uranium with 164 centrifuges, a step toward large-scale production.

China responded by expressing strong concern over Iran's announcement and called on Tehran to suspend enrichment.

Both China and Russia oppose punitive measures against Iran.

The United States and Britain say that if Iran does not comply with the Security Council's demand to stop enrichment by April 28, they will seek a resolution that would make the demand compulsory