diff --git a/include/psa/crypto_extra.h b/include/psa/crypto_extra.h
index 2ac2c5b..f0c7979 100644
--- a/include/psa/crypto_extra.h
+++ b/include/psa/crypto_extra.h
@@ -645,17 +645,6 @@
                                                size_t byte_length );
 #endif /* MBEDTLS_ECP_C */
 
-/** Convert an mbed TLS error code to a PSA error code
- *
- * \note This function is provided solely for the convenience of
- *       Mbed TLS and may be removed at any time without notice.
- *
- * \param ret           An mbed TLS-thrown error code
- *
- * \return              The corresponding PSA error code
- */
-psa_status_t mbedtls_to_psa_error( int ret );
-
 /**@}*/
 
 #ifdef __cplusplus
diff --git a/library/psa_crypto_core.h b/library/psa_crypto_core.h
index 9a61bab..6ee17fc 100644
--- a/library/psa_crypto_core.h
+++ b/library/psa_crypto_core.h
@@ -161,4 +161,16 @@
                                        const uint8_t *data,
                                        size_t data_length );
 
+
+/** Convert an mbed TLS error code to a PSA error code
+ *
+ * \note This function is provided solely for the convenience of
+ *       Mbed TLS and may be removed at any time without notice.
+ *
+ * \param ret           An mbed TLS-thrown error code
+ *
+ * \return              The corresponding PSA error code
+ */
+psa_status_t mbedtls_to_psa_error( int ret );
+
 #endif /* PSA_CRYPTO_CORE_H */
diff --git a/tests/src/drivers/keygen.c b/tests/src/drivers/keygen.c
index 7f14b20..4f30f0e 100644
--- a/tests/src/drivers/keygen.c
+++ b/tests/src/drivers/keygen.c
@@ -25,6 +25,7 @@
 
 #if defined(MBEDTLS_PSA_CRYPTO_DRIVERS) && defined(PSA_CRYPTO_DRIVER_TEST)
 #include "psa/crypto.h"
+#include "psa_crypto_core.h"
 #include "mbedtls/ecp.h"
 #include "mbedtls/error.h"
 
diff --git a/tests/src/drivers/signature.c b/tests/src/drivers/signature.c
index 62ba407..04c5de4 100644
--- a/tests/src/drivers/signature.c
+++ b/tests/src/drivers/signature.c
@@ -25,6 +25,7 @@
 
 #if defined(MBEDTLS_PSA_CRYPTO_DRIVERS) && defined(PSA_CRYPTO_DRIVER_TEST)
 #include "psa/crypto.h"
+#include "psa_crypto_core.h"
 #include "mbedtls/ecp.h"
 
 #include "drivers/signature.h"