Visa Developer has an API Availability Matrix that shows the availability of all our APIs. The matrix lets you know which countries/regions that the API is available to be used in, however, it won't show you what countries are banned. I don't have a list of banned countries readily available to provide you at this time. Please use this link to the matrix which will be helpful in answering your question - https://developer.visa.com/availability
Please note that the matrix shows the availability for each API per region, so you will need to click on the region to see the availability of the APIs for that region. For example, if you want to see the regional availability of APIs for Asia-Pacific then you will need to click on the Asia-Pacific tab.
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