Iran’s top nuclear negotiator is heading to China for talks on Thursday as Western governments become increasingly confident that Beijing will back sanctions against Iran over its disputed nuclear activities.

WHAT IS CHINA’S GENERAL POSITION ON SANCTIONS?

China has long said sanctions are not an effective tool to solve diplomatic disputes, and its diplomats have often repeated that line in answering questions about Iran.

That position partly reflects Beijing’s resentment of Western sanctions it has faced, especially after the 1989 armed crackdown on pro-democracy protests around Tiananmen Square.

It also chimes with China’s stance of “non-interference” in other nations’ domestic affairs, a position that has often amounted to wanting to insulate its economic interests from diplomatic disputes.

But Beijing has backed previous rounds of U.N. sanctions against North Korea and Iran over their disputed nuclear activities. China this year also threatened to put unilateral sanctions on U.S. firms selling weapons to Taiwan, the self-ruled island that Beijing claims as its own.

Since the 1990s, China has cast itself as a responsible supporter of nuclear non-proliferation safeguards.

That desire to be a respected global player and not be isolated from dominant international opinion could weigh in favour of China allowing fresh sanctions against Iran, especially with Russia indicating it may back sanctions.

HOW WILL CHINA HANDLE THE NEW SANCTIONS PUSH AGAINST IRAN?

China is one of five permanent members of the U.N. Security Council with the power to veto any proposed resolution.

While Beijing sometimes abstains from Security Council votes on decisions it dislikes, it is much less willing to use its veto and risk diplomatic isolation, especially if fellow Security Council member Russia backs a resolution.

China is more likely to use its influence to draw out negotiations on sanctions and try to thwart any measures that could threaten its energy and economic ties with Iran, as it has done before.

In July 2006, China backed U.N. Security Council Resolution 1696 that threatened sanctions on Iran, and in December of the same year it supported Resolution 1737, which imposed sanctions on Iranian nuclear imports and exports.

It supported two further resolutions, one in 2007 which broadened the sanctions to cover a ban on Iranian arms exports, and another in 2008 which criticised Iran for refusing to suspend uranium enrichment.

Each time, however, Beijing has worked to rein in Western demands for tougher restrictions on Tehran.

A draft sanctions document circulated by Western powers a few weeks ago proposes restricting more Iranian banks abroad, but does not call for sanctions against Iran’s oil and gas industries.

WHY IS CHINA OPPOSED TO STRICT ECONOMIC SANCTIONS?

Beijing sees Iran as an important oil supplier and trade partner and as a major strategic actor in the Middle East, where China is buying growing volumes of oil. There is scant chance of China risking those ties by backing expansive economic sanctions.

China is the world’s No. 2 crude oil consumer, behind the United States. Iran has the world’s second-largest crude oil reserves, but needs investment to develop them.

In 2009, Iran was China’s third biggest source of imported crude oil. But in the first two months of 2010, China imported 2.53 million metric tonnes of Iranian crude oil, a drop of 37.2 percent compared to the first two months of 2009.

That made Iran the fourth-ranked foreign source of crude for China so far this year, behind Russia, Angola and top supplier, Saudi Arabia.

China is also an investor in Iranian oil and gas, and Chinese state-owned energy conglomerates have been exploring for new fields there, with an eye to expanding their stake.

Industry sources have said China has been selling gasoline to Iran, which lacks refining capacity to meet domestic demand. Chinese customs statistics do not record any shipments, which may go through intermediaries.

(Editing by Sanjeev Miglani)