How US trying to wean China off Iranian oil

The United States collaborated with Saudi Arabia to increase crude oil supplies to China at the expense of Iran, US diplomatic cables show. The move was designed to hurt Iran and win Beijing's support for sanctions against Tehran over its nuclear programme.
China has long worried that oil supplies from Iran could be choked off if Beijing sides too closely with the West over Tehran's disputed nuclear activity, which opponents say is intended to give it the means to assemble nuclear weapons. Iran insists its nuclear programme is peaceful.
But as Saudi deliveries of crude increased to China over the past years, so has Beijing's support for UN sanctions against Tehran - although Chinese state oil conglomerates have been moving into the vacuum created by the withdrawal of most major players from the Iranian oil patch.
The cables, obtained by WikiLeaks and provided to Reuters by a third party, lay out how US diplomats worked with Saudi Arabia and other big Middle Eastern oil suppliers to persuade Beijing to back tougher sanctions on Iran. Saudi Arabia and the United States discussed how increasing Saudi crude supplies to China "would have the welcome side impact of reducing Iranian leverage over China", US officials told the Saudi Oil Minister Ali Al-Naimi in August 2009.
Two months earlier, a senior French diplomat overseeing Middle Eastern affairs told a US embassy official that Saudi diplomats had told China: "If you want oil from us ... then you must put more pressure on Iran."
For Saudi Arabia, increasing crude exports to China also made economic sense. Saudi oil sales to China were growing in response to increasing demand, and the Kingdom wanted to diversify its customers just as China and many other countries wanted to diversify energy supplies and suppliers, Al-Naimi told US officials according to a cable dated August 2009.
Saudi Arabia is now China's biggest source of oil and the kingdom delivers more oil to China now than it does to the United States. Once Saudi Arabia began stepping up oil deliveries to China, Beijing began urging Iran to take seriously western proposals for ways to end the nuclear stand-off.
China's Foreign Minister Yang Jiechi told the US ambassador to the United Nations Susan Rice in a June 2009 meeting that "China urged Iran more than once to be forthcoming with the US 'in many areas'." Yang also said he believed, regardless of Iran's rhetoric, that "deep down" Tehran must be impressed by President Obama's willingness to work together. That meeting was one of several instances which illustrated how China acted as a go-between for Washington with Iran, or was asked to be one.
On October 16, 2009, the US ambassador to the International Atomic Energy Agency, Glyn Davies, asked his Chinese counterpart Hu Xiaodi to persuade Iran to send a high-level Iranian delegation to an IAEA meeting in Vienna. Hu replied it would be "odd" for China to pass along that suggestion, given China itself was not attending that meeting, according to one diplomatic cable.
The UN Security Council has imposed four rounds of sanctions on Tehran for refusing to freeze its uranium enrichment programme. The sanctions have so far excluded oil and gasoline exports. However, last year, the United States and the European Union approved a wide range of sanctions that hit the heart of Iran's lucrative energy sector.