Treasury Secretary Timothy Geithner, visiting Beijing this week, is likely to find China resistant to putting financial pressure on the government in Tehran. (Jason Reed/Reuters)

Treasury Secretary Timothy F. Geithner, visiting Beijing this week, is expected to press China’s leaders to reduce the country’s oil imports from Iran. But Geithner is likely to find Beijing resistant to putting financial pressure on the government in Tehran.

In a briefing for reporters Monday, Cui Tiankai, the vice foreign minister responsible for U.S. relations, said that China supports global nonproliferation efforts but that trade is separate from the Iranian nuclear issue.

“The normal trade relations and energy cooperation between China and Iran have nothing to do with the nuclear issue,” Cui said. “We should not mix issues of different natures, and China’s legitimate concerns and demands should be respected.”

Cui noted that some have argued that any normal business dealings with Iran provided financial support for its nuclear program, but he said, “This argument does not hold water.”

“According to this logic, if the Iranians have enough money to feed their population, then they have the ability to develop nuclear programs,” Cui told reporters. “If that is the case, should we also deny Iran the opportunity to feed its population?”

Energy-hungry China imported 11 percent of its oil from Iran last year, with Chinese purchases reaching a high of about 617,000 barrels a day in November. According to figures from China’s customs office, the oil purchases from Iran last year were significantly higher than those in the previous year on a month-to-month comparison. Iran sent roughly a third of its oil exports to China.

But in December and so far this year, the imports appear to have slowed, primarily because of a dispute over pricing and credit terms. The January imports were roughly half of the 2011 daily average, industry analysts said.

A new U.S. law would penalize foreign companies that deal with the Central Bank of Iran, which handles the country’s oil revenue. Geithner’s visit to China, to be followed by a stop in Japan later this week, is aimed at getting Iran’s main Asian oil consumers to at least reduce, if not stop, their imports of Iranian oil.

Iranian officials, meanwhile, have threatened to retaliate against any efforts to curtail oil shipments by blocking the strategic Strait of Hormuz, through which passes roughly 35 percent of the world’s oil shipments, or nearly 20 percent of the oil traded worldwide. Defense Secretary Leon E. Panetta, in an interview Sunday on CBS’s “Face the Nation,” said, “We made very clear that the United States will not tolerate the blocking of the Straits of Hormuz.”

The latest tension in the Persian Gulf comes as Iranian President Mahmoud Ahmadinejad traveled Sunday to Venezuela at the start of a Latin America tour aimed at showing that Iran still has supporters and economic partners in the world.

Also, reports surfaced in Iran’s media over the weekend that the country has begun to enrich uranium at a new underground facility, built to withstand possible airstrikes.

And Monday, Iran’s revolutionary court, in a preliminary ruling, convicted an Iranian American, Amir Mirzaei Hekmati, 28, of spying and sentenced him to death, in a decision likely to ratchet up tensions with Washington.

In the Monday briefing, Cui, the Chinese vice foreign minister, said China supported efforts to stop the spread of nuclear weapons and had “upheld [U.N.] Security Council resolutions and faithfully implemented them.”

“We support upholding the nonproliferation regime,” Cui said, adding that Iran had the right to develop peaceful nuclear power. “This issue cannot be resolved by sanctions alone. It must also be solved through negotiation.” He added, “We also hope to see significant progress on the negotiation track.”

In the briefing, he also took issue with Republican presidential candidates in the United States who have repeatedly singled out China as a rhetorical target , accusing Beijing of keeping its currency artificially low — and costing Americans jobs — as well as stealing intellectual property, condoning computer hacking and engaging in unfair trade practices. GOP front-runner Mitt Romney has been particularly tough, promising to label China a “currency manipulator” on his first day in office.

“These people who keep mentioning China’s name in the presidential campaign,” Cui said, “how much knowledge do they have about the U.S.-China relationship?”

“One thing is clear,” he said. “To ensure healthy and stable relations serves both China and the U.S.” He said that throughout history — beginning with President Richard M. Nixon’s visit to China 40 years ago — American presidents from both parties have kept U.S.-China relations on a steadily improving path.

China also took issue Monday with the Obama administration’s new military strategy, unveiled last week at the Pentagon, which shifts the focus of the U.S. armed forces to the Asia-Pacific region, to counter China’s rising influence in the region.

“Although different presidents have been in office, the China policy of the administrations has been fairly consistent,” Cui said. “I see no reason we should disrupt or stop this trend.”

Cui said that despite a few “hot-spot issues,” the Asia-Pacific region was, on the whole, “stable and peaceful,” and that Asian countries wanted to concentrate on their economic development. “I don’t think military alliances is what they need most.”

“The U.S. has the strongest military in the world and spends more than any other country,” Cui said. “But the U.S. always feels unsafe or insecure about other countries.” He added, “I suggest the United States spend more time thinking about how to make other countries feel less worried about the United States.”

Earlier Monday, a Chinese Foreign Ministry spokesman used a regularly scheduled briefing to criticize the new U.S. defense posture.

“China’s strategic intent is clear, open and transparent,” the spokesman, Liu Weimin, told reporters.

“Our national defense modernization serves the objective requirements of national security and development and also plays an active role in maintaining regional peace and stability. It will not pose any threat to any country,” Liu said. “The charges against China in this document are groundless and untrustworthy.”

The Chinese Defense Ministry echoed a similar theme in comments Monday. “The accusations leveled at China by the U.S. side in this document are totally baseless,” said the Defense Ministry spokesman, Geng Yansheng.