"The specified blob does not exist" when trying to copy blob between storage accounts

I’m writing a script to copy blobs from one Azure Blob Storage Container to another; potentially in a different storage account. The gist of how I’m doing that is below:

const sourceBlobClient = BlobServiceClient.fromConnectionString(sourceConnectionString);
const sourceContainer = sourceBlobClient.getContainerClient(sourceContainerName);

const targetBlobClient = BlobServiceClient.fromConnectionString(targetConnectionString);
const targetContainer = targetBlobClient.getContainerClient(targetContainerName);

const blobName = 'something';

const sourceBlobClient = sourceContainer.getBlobClient(blobName);
const targetBlobClient = targetContainer.getBlobClient(sourceBlobClient.name);

const copyResponse = await targetBlobClient.beginCopyFromURL(sourceBlobClient.url);
// Wait on copyResponse

When testing this locally and copying between two Azure containers in a Docker Azurite container with the same Storage Account, it works fine.

In reality though, the source and destination will be on different machines on different Storage Accounts. When I run the same code (replacing the connection string of the source to be a remote machine), I get an error (pasting the last part of a very long message):

details: {
  errorCode: 'BlobNotFound',
  connection: 'keep-alive',
  'content-type': 'application/xml',
  date: '<. . .>',
  'keep-alive': 'timeout=5',
  server: 'Azurite-Blob/3.23.0',
  'transfer-encoding': 'chunked',
  'x-ms-request-id': '<. . .>',
  message: 'The specified blob does not exist.\n' +
    'RequestId:<. . .>\n' +
    'Time:<. . .>',
  code: 'BlobNotFound'
}

The blob definately exists in the remote source (its name was pulled from a call to listBlobsFlat).

I’m unsure of the cause of this. The docs seem to suggest that copying between accounts is now possible (this text is repeated in the beginCopyFromURL docs):

In version 2012-02-12 and later, the source for a Copy Blob operation can be a committed blob in any Azure storage account.

Am I misinterpreting the docs? Is there something else going on here?

>Solution :

For copying blob across storage accounts, source blob must be publicly accessible. Please create a SAS URL for the source blob with at least “read” permission and use that URL for copying.