diff --git a/library/legacy_or_psa.h b/library/legacy_or_psa.h
index 84fc206591..be0f33f82e 100644
--- a/library/legacy_or_psa.h
+++ b/library/legacy_or_psa.h
@@ -90,6 +90,9 @@
 #define MBEDTLS_OR_PSA_HELPERS_H
 
 #include "common.h"
+#if defined(MBEDTLS_PSA_CRYPTO_C)
+#include "psa/crypto.h"
+#endif /* MBEDTLS_PSA_CRYPTO_C */
 
 /*
  * Hashes