China has defended its business ties with Iran after a United States official urged Beijing to fully implement sanctions against Tehran.
China Thursday rejected concerns about its dealings with Iran.
China's state media quoted a Foreign Ministry spokeswoman saying trade with Tehran is normal business and does not harm the interests of other countries or the international community.
She was responding to comments made by the United States' special advisor for nonproliferation and arms control, Robert Einhorn.
This week Einhorn said China should fully cooperate with United Nations sanctions imposed against North Korea and Iran because of their nuclear programs.
The U.S. and European Union recently passed new sanctions against Iran and are encouraging Russia and China to support them. The sanctions target Iran's energy and banking sectors.
Joseph Cheng, a professor of political science at Hong Kong's City University, says Beijing has little interest in new sanctions.
"China certainly has substantial oil interests in Iran and therefore China is quite reluctant to support the American position," he said. "On the other hand, of course, the American government realizes that unless all major powers are in concerted action, otherwise sanctions will be largely ineffective, it may even hurt the interests of American corporations."
As Western businesses have pulled out of Iran because of the sanctions, concerns have been raised that Chinese enterprises are moving in to snatch up business.
China is already Iran's biggest trading partner and plans to invest billions of dollars in its oil sector, including building several refineries.
Tehran is energy-hungry China's third largest oil supplier. Iran's oil minister is in China this week to discuss further trade and cooperation.
Although trade relations are friendly, Cheng says China is concerned about Iranian nuclear proliferation, and in June supported a fourth round of U.N. sanctions against Iran.
China's Foreign Ministry says the country has always observed the Security Council's resolutions and rejects suggestions that Beijing is not acting responsibly.
But Beijing has opposed tougher measures, including unilateral sanctions imposed by the U.S., EU, Australia, Canada, and Japan, who fear that Tehran aims to acquire nuclear weapons. Iran says its nuclear programs are for peaceful energy purposes.
Despite the sanctions, Iran last month claimed to have acquired an advanced missile system, bringing into question the effectiveness of the measures.