diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 2bbe3a5..b576f95 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -3969,9 +3969,13 @@
     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
     size_t required_hash_length;
 
-    if (!PSA_KEY_TYPE_IS_ECC(attributes->type)) {
+    if (!PSA_KEY_TYPE_IS_ECC_KEY_PAIR(attributes->type)) {
         return PSA_ERROR_NOT_SUPPORTED;
     }
+    psa_ecc_family_t curve = PSA_KEY_TYPE_ECC_GET_FAMILY(attributes->type);
+    if (!PSA_ECC_FAMILY_IS_WEIERSTRASS(curve)) {
+        return PSA_ERROR_INVALID_ARGUMENT;
+    }
 
     if (!can_do_interruptible_sign_verify(alg)) {
         return PSA_ERROR_NOT_SUPPORTED;
@@ -4188,6 +4192,10 @@
     if (!PSA_KEY_TYPE_IS_ECC(attributes->type)) {
         return PSA_ERROR_NOT_SUPPORTED;
     }
+    psa_ecc_family_t curve = PSA_KEY_TYPE_ECC_GET_FAMILY(attributes->type);
+    if (!PSA_ECC_FAMILY_IS_WEIERSTRASS(curve)) {
+        return PSA_ERROR_INVALID_ARGUMENT;
+    }
 
     if (!can_do_interruptible_sign_verify(alg)) {
         return PSA_ERROR_NOT_SUPPORTED;