diff --git a/scripts/mbedtls_dev/build_tree.py b/scripts/mbedtls_dev/build_tree.py
index da455a7f2..f506c4142 100644
--- a/scripts/mbedtls_dev/build_tree.py
+++ b/scripts/mbedtls_dev/build_tree.py
@@ -32,6 +32,16 @@ def crypto_core_directory(root: Optional[str] = None) -> str:
     else:
         raise Exception('Neither Mbed TLS nor TF-PSA-Crypto source tree found')
 
+def project_crypto_name(root: Optional[str] = None) -> str:
+    if root is None:
+        root = guess_project_root()
+    if looks_like_tf_psa_crypto_root(root):
+        return "tfpsacrypto"
+    elif looks_like_mbedtls_root(root):
+        return "mbedcrypto"
+    else:
+        raise Exception('Neither Mbed TLS nor TF-PSA-Crypto source tree found')
+
 def check_repo_path():
     """
     Check that the current working directory is the project root, and throw
diff --git a/tests/scripts/test_psa_compliance.py b/tests/scripts/test_psa_compliance.py
index 2482d032a..82cc1b1db 100755
--- a/tests/scripts/test_psa_compliance.py
+++ b/tests/scripts/test_psa_compliance.py
@@ -50,10 +50,7 @@ def main(library_build_dir: str):
 
     in_tf_psa_crypto_repo = build_tree.looks_like_tf_psa_crypto_root(root_dir)
 
-    if in_tf_psa_crypto_repo:
-        crypto_name = 'tfpsacrypto'
-    else:
-        crypto_name = 'mbedcrypto'
+    crypto_name = build_tree.project_crypto_name()
 
     library_subdir = build_tree.crypto_core_directory()