PetroChina bought 1 million barrels of crude oil settled in e-CNY, or digital yuan, at the Shanghai Petroleum and Natural Gas Exchange (SHPGX) on Oct. 18, according to the report by the Chinese Communist Party-owned newspaper.

The SHPGX did not disclose the exact value of the deal nor the seller’s identity.

China’s government may wish to use the e-CNY as a tool for expanding the international use of its currency, also known as the renminbi, so using it to settle purchases of major global commodities like crude oil would be one way to underpin this expansion.

While almost all the world’s major economies are at least looking at developing a CBDC, China’s is comfortably among the most advanced. Transactions using the currency hit 1.8 trillion yuan ($250 billion) as of the end of June, with e-CNY accounting for 0.16% of the cash in circulation.

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