diff --git a/tf-psa-crypto/core/psa_crypto_core.h b/tf-psa-crypto/core/psa_crypto_core.h
index 5f59697612..a3c0fd6f19 100644
--- a/tf-psa-crypto/core/psa_crypto_core.h
+++ b/tf-psa-crypto/core/psa_crypto_core.h
@@ -56,9 +56,12 @@ typedef enum {
 } psa_key_slot_state_t;
 
 /* If the size of static key slots is not explicitly defined by the user, then
- * set it to PSA_EXPORT_KEY_PAIR_OR_PUBLIC_MAX_SIZE. */
+ * set it to the maximum between PSA_EXPORT_KEY_PAIR_OR_PUBLIC_MAX_SIZE and
+ * PSA_CIPHER_MAX_KEY_LENGTH. */
 #if !defined(MBEDTLS_PSA_STATIC_KEY_SLOT_BUFFER_SIZE)
-#define MBEDTLS_PSA_STATIC_KEY_SLOT_BUFFER_SIZE        (PSA_EXPORT_KEY_PAIR_OR_PUBLIC_MAX_SIZE)
+#define MBEDTLS_PSA_STATIC_KEY_SLOT_BUFFER_SIZE  \
+    (PSA_EXPORT_KEY_PAIR_OR_PUBLIC_MAX_SIZE > PSA_CIPHER_MAX_KEY_LENGTH) ? \
+    PSA_EXPORT_KEY_PAIR_OR_PUBLIC_MAX_SIZE : PSA_CIPHER_MAX_KEY_LENGTH
 #endif /* !MBEDTLS_PSA_STATIC_KEY_SLOT_BUFFER_SIZE*/
 
 /** The data structure representing a key slot, containing key material