A top Chinese diplomat on Monday rejected linking Iran's nuclear program to trade, adding to tensions with Washington on the eve of a visit by U.S. Treasury Secretary Timothy Geithner to seek support for sanctions on Tehran's oil industry.
A deputy foreign minister, Cui Tiankai, said China's trade with Iran, an important oil supplier, has nothing to do with the Iranian nuclear program.
Washington is pressuring Tehran to abandon what Western governments say is an effort to develop nuclear weapons. Sanctions approved by President Barack Obama on New Year's Eve would bar financial institutions that deal with Iran's central bank from the U.S. market.
"The normal trade relations and energy cooperation between China and Iran have nothing to do with the nuclear issue," Cui told reporters. "We should not mix issues with different natures, and China's legitimate concerns and demands should be respected."
China's fast-growing economy is the world's biggest energy consumer and obtained about 11 percent of its oil imports from Iran last year. Industry analysts say Beijing is unlikely to support an oil embargo against Iran because such huge imports would be next to impossible to obtain from other sources.
The sanctions have led to a clash of interests between Washington and key commercial and strategic partners in Asia.
South Korea and Japan also depend on Iranian oil and are negotiating with Washington in an effort to keep supplies flowing. South Korea obtains up to 10 percent of its oil from Iran, while Japan gets nearly 9 percent.
The dispute threatens to add to irritants in U.S.-Chinese ties, which are strained by disputes over market access and pressure on Beijing to ease currency controls that Washington complains are swelling its trade surplus.
"We feel strongly that all countries including China ought to be looking hard at how we can reduce dependence on Iranian oil as a way to send a signal to that government that it needs to come back under compliance with its international obligations," U.S. State Department spokeswoman Victoria Nuland told a news briefing in Washington.
Cui, one of the top officials in charge of relations with Washington, said Beijing supports nuclear nonproliferation efforts but believes Iran is entitled to develop peaceful atomic energy.
He rejected suggestions that anyone who does business with Iran is providing money for nuclear programs.
"According to this logic, if the Iranians have enough money to feed their population, then they have the ability to develop nuclear programs. If that is the case, should we also deny Iran the opportunity to feed its population?" he said.
"We believe the livelihood of the Iranian people and the normal economic ties between countries in the world and Iran should not be affected."
Chinese purchases of Iranian crude averaged about 560,000 barrels per day in 2011, rising to 617,000 barrels in November, close to one-third of Iran's total exports of 2.2 million barrels per day, according to oil industry analysts Argus Media.
Associated Press writer Matthew Pennington in Washington contributed to this report.