When the world relies on a single reserve currency, Triffin argued, that currency's home country must issue lots of assets (usually government bonds) to lubricate global commerce and meet the demand for reserves.

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Second, the country that issues the reserve currency faces a trade-off between domestic and international stability.

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"International supervision over the issue of US dollars should be introduced and a new, stable and secured global reserve currency may also be an option to avert a catastrophe caused by any single country, " the commentary said.

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The U.S. was the first country to be accused of waging currency war, when Brazil objected to the Federal Reserve's second round of quantitative easing in 2011, which was widely seen as a naked attempt to drive down the dollar.

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In a country that has locked itself out of international markets, U.S. dollars, the global reserve currency, are hard to come by.

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