Saudi Arabia’s central bank has joined Project mBridge – a cross-border experiment with central bank digital currencies (CBDCs) for international trade – as a full participant, the Switzerland-based Bank for International Settlements (BIS) announced Wednesday.

Project mBridge was launched in 2021 as a collaboration between the BIS’ innovation arm and the central banks of China, Hong Kong, Thailand and the United Arab Emirates (UAE) to test the viability of CBDCs for instantaneous cross-border trade and other payments using the project’s blockchain, the mBridge Ledger.

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BIS also announced Wednesday that Project mBridge has, after three years, reached the minimum viable product (MVP) stage and has requested private sector financial firms to “propose new solutions and use cases that help develop the platform and showcase all its potential.”

In addition to mBridge’s six full participants, 27 other official entities – including the International Monetary Fund (IMF), the World Bank and the central banks of countries including Norway, South Korea and Turkey – have signed on as observers to the project, giving them access to a “sandbox” for experimentation with the technology.

Major global financial institutions, including Goldman Sachs, HSBC and China’s six biggest state-owned banks, are also working on the project.