What Russia-China relations mean for the dollar
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If there was one takeaway from Russia's annual economic shindig in St Petersburg last week, it was that the country is continually looking to its neighbor China for trade and investment. While the United States can't claim that it might be losing a friend with Russia's pivot east, it might be a different story for the dollar (Exchange:.DXY), with the alliance having the potential to undercut the domination of the U.S. currency.

"Taken alone, these actions do not mean the end of the dollar as the leading global reserve currency. But, taken in the context of many other actions around the world including Saudi Arabia's frustration with U.S. foreign policy toward Iran, and China's voracious appetite for gold (Exchange:XAU=), these actions are meaningful steps away from the dollar," Jim Rickards, portfolio manager at West Shore Group and partner at Tangent Capital Partners, told CNBC via email.

Speaking at a CNBC-hosted event on Friday, Russian President Vladimir Putin outlined his plans for closer links with China and a new Eurasian union. This followed a high-profile deal by Gazprom, the Russian state-backed gas giant, which signed a $400 billion, 30-year deal to supply gas to China.

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The deal looks promising for Moscow, with Europe - the traditional buyer of its oil - hoping to wean itself off Russian dependency, especially with recent tensions following Russia's annexation of Crimea.

Despite the details for the deal being scarce, many analysts predict that the oil exports would mean Chinese yuan (Exchange:CNY=) being exchanged directly, into the Russian ruble (Exchange:RUB=). Thus the two countries would bypass the U.S. dollar - the traditional currency used in oil trades and considered to be the international reserve currency of choice.

Medvedev promotes ruble

Meanwhile, VTB (Moscow Interbank Currency Exchange: VTBR-MZ), Russia's second biggest bank, has signed a deal with Bank of China that includes an agreement to pay each other in domestic currencies. Added to this, Russian Prime Minister Dmitry Medvedev spoke on Russian TV over the weekend saying sanctions imposed on the country by the EU and U.S. would make Russia use the ruble for trade and would eventually turn it from a "convertible into a reserve currency."

With the two developing nations trading outside of the U.S. dollar, many questions are being raised about what this would do for the greenback and for the U.S. The dollar's status as the global reserve currency has allowed the U.S. to borrow large sums of money, effectively living beyond its means, because there is always a demand for its currency.