BEIJING China's silence sometimes speaks volumes, and with growing international momentum for new sanctions on Iran, Beijing's recent reticence suggests it may give ground if it can insulate its oil and business ties.
China has repeatedly said in recent months that expanded U.N. sanctions on Iran are not the way to draw Tehran into serious talks about curtailing its uranium enrichment programme, which Western powers say could lay the groundwork for a nuclear weapons capability.
Not of late.
Chinese Foreign Minister Yang Jiechi last week urged more diplomacy with Iran, but did not say whether China backed or opposed fresh sanctions.
At two Chinese Foreign Ministry briefings this week, spokesman Ma Zhaoxu avoided extensive comment, positive or negative, about the sanctions proposed by the West.
"On sanctions, our position has been consistent and clear," Ma told reporters on Thursday. "We are willing, together with the international community, to continue playing a constructive role in pushing for a resolution of the Iran nuclear issue."
China can use its power as one of the five permanent members of the U.N. Security Council to veto any resolution authorising sanctions.
"China's silence says it isn't strongly opposed to a new United Nation's resolution," said Yin Gang, an expert on the Middle East at the Chinese Academy of Social Sciences, a prominent state think-tank in Beijing.
"Given Iran's increasingly hard line on the nuclear issue, China feels it can't stand in the way of some sort of international response," he added.
Iran defied international pressure by announcing over the weekend that it would enrich uranium to 20 percent purity for a reactor, and on Thursday said it had produced its first consignment of the product.
With Russia also irked by Iran, Beijing may cautiously back a new Security Council resolution on Iran, or let it pass by abstaining from the vote, avoiding isolation from other big powers.
ENERGY SANCTIONS WOULD HURT CHINA
Beijing will nonetheless resist expansive sanctions against Iran, China's third-biggest supplier of imported crude oil after Angola and top supplier Saudi Arabia, said Jin Liangxiang, a researcher at the Shanghai Institute for International Studies who is a specialist on the Middle East.
Some Western diplomats have said they would like sanctions to cover Iran's energy sector.
"Fully going with Western expansion of sanctions on Iran so they restrict Iran's energy exports would amount to disguised sanctions against China, and China certainly won't agree," Wang Feng, a researcher at the Chinese Academy of Social Sciences told the Global Times, a Chinese newspaper published on Thursday.
Beijing probably figures it can pare back a proposed U.N. resolution so Western powers can then claim a united international front while Chinese energy and economic ties to Iran are protected.
"I'd expect very tough and drawn out (Security Council) negotiations, and a unified international stance is not assured," said Jin, the Shanghai-based expert.
But by giving some ground to Western powers, Beijing would avoid adding to recent strains with the United States.
Washington has criticised China over Internet controls and trade imbalances, while Beijing has threatened to punish Washington over planned arms sales to Taiwan, the self-ruled island off the mainland coast that China claims as its own.
But China's Communist Party leaders will also want to handle carefully domestic public ire at the United States.
The Obama administration's plan to sell a new package of weapons to Taiwan has prompted calls from Chinese military officers and angry citizens for hard-hitting retaliation against Washington.
The Global Times, a tabloid that often dwells on nationalist themes, said on Thursday that in an Internet survey it organised, 70 percent of some 10,000 respondents said China should veto any new U.N. resolution on Iran.
Beijing must also heed the views of Arab states, especially Saudi Arabia, which have shown growing impatience with Tehran, said Yin, the Middle East expert.
"China knows the Iran nuclear issue is now a global issue, so using it as a pawn to bargain with the United States over Taiwan is not credible," he said. "China may voice its anger, but it won't tie the two issues together," he added.
(Additional reporting by Ben Blanchard; Editing by Jeremy Laurence)