BEIJING (Reuters) - China pushed back at U.S. pressure on its business and oil trade with Iran in comments published on Wednesday, while Iran's oil minister was in Beijing seeking to shore up ties with the big customer.

Chinese Foreign Ministry spokeswoman Jiang Yu was responding to comments by Robert Einhorn, special adviser for nonproliferation and arms control at the U.S. State Department, who said on Monday China should observe sanctions against Iran aimed at forcing it to curtail its nuclear ambitions.
Western governments have pressed China to loosen its energy and economic ties with Iran, which they see as shielding Iran from international pressure.
Iran's oil minister, Massoud Mirkazemi, is in Beijing for talks with Chinese energy executives. He has not made any public comments.
Jiang, the Chinese spokeswoman, said her country's trade dealings with Iran should not be criticized.
""China's trade with Iran is a normal business exchange, which will not harm the interests of other countries and the international community,"" she said in comments published in the official China Daily.
""As a permanent member of the UN Security Council, China has always observed the council's resolutions,"" she said.
Iran is a major supplier of crude oil to China, the world's second-biggest consumer of oil after the United States.
The United States has urged China to tap other suppliers, but China has condemned unilateral U.S. and EU sanctions aimed at Iran's energy sector.
China has backed UN Security Council resolutions pressing Iran to abandon disputed nuclear activities.
The latest resolution was passed in June.
But China has also wielded its veto power over Council resolutions to protect energy and trade flows with Iran.
In the first half of 2010, Iran held its place as China's third biggest supplier of crude with shipments of 9 million tons of oil, putting it behind Saudi Arabia and Angola, according to Chinese customs data.