China-ASEAN cross-border RMB settlement volume has surged nearly 20-fold in the past decade, according to a report released on Saturday during the ongoing 19th China-ASEAN Expo.

RMB settlement volume between China and the Association of Southeast Asian Nations (ASEAN) reached 4.8 trillion yuan ($687 billion) in 2021, a year-on-year increase of 16 percent, data from the People's Bank of China (PBOC) backed Financial Society of Guangxi showed.

China-ASEAN monetary authorities are in close contact in upgrading multi-currency cooperation, said Chen Jinxiang, president of the Nanning branch of the PBOC along the release of the report.

By the end of 2021, China had signed separate bilateral currency settlement agreements with Vietnam, Indonesia, and Cambodia in local currencies, as well as currency swap agreements with countries including Indonesia, Malaysia, Singapore and Thailand worth about 800 billion yuan, said Chen.

He added that the payment and clearing network continues to improve between China-ASEAN.

The RMB-based Cross-Border Interbank Payment System handled 3.3 trillion yuan of China-ASEAN trade in 2021, a yearly surge of more than 50 percent.

Looking ahead, Chen said geopolitical conflicts and global inflation will continue to add to the economic and financial uncertainties, fuel calls for creating a more diversified, fair and reciprocal international monetary system.

Trade between China and ASEAN sustained rapid growth over the years, setting the stage for RMB's usage as a currency in settlements.

China has been ASEAN's largest trading partner for 13 consecutive years. In the first eight months, the country's imports and exports with the bloc hit 4.09 trillion yuan, an increase of 14 percent compares with the same period last year, accounting for 15 percent of the total foreign trade value, customs data showed.

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