China's deputy UN ambassador Liu Zhenmin made the comments at a UN Security Council meeting Wednesday after the chair of the committee monitoring three rounds of sanctions against Iran presented a report.

Key Western powers including the United States are pushing for a fourth round of sanctions because of Iran's refusal to halt uranium enrichment and have sent a revised proposal to Russia and China.

But China's Lu said the door to dialogue with Tehran has not closed, and he called on Iran to strengthen cooperation with the International Atomic Energy Agency to remove doubts about its nuclear intentions.