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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