diff --git a/tests/src/psa_crypto_helpers.c b/tests/src/psa_crypto_helpers.c
index 40877c7..dacda68 100644
--- a/tests/src/psa_crypto_helpers.c
+++ b/tests/src/psa_crypto_helpers.c
@@ -27,4 +27,20 @@
 
 #include <psa/crypto.h>
 
+#if defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
+#include <test/random.h>
+
+psa_status_t mbedtls_psa_external_get_random(
+    mbedtls_psa_external_random_context_t *context,
+    uint8_t *output, size_t output_size, size_t *output_length )
+{
+    /* This implementation is for test purposes only!
+     * Use the libc non-cryptographic random generator. */
+    (void) context;
+    mbedtls_test_rnd_std_rand( NULL, output, output_size );
+    *output_length = output_size;
+    return( PSA_SUCCESS );
+}
+#endif /* MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
+
 #endif /* MBEDTLS_PSA_CRYPTO_C */
diff --git a/tests/suites/test_suite_psa_crypto_init.function b/tests/suites/test_suite_psa_crypto_init.function
index 62ef6e2..867e423 100644
--- a/tests/suites/test_suite_psa_crypto_init.function
+++ b/tests/suites/test_suite_psa_crypto_init.function
@@ -17,6 +17,8 @@
 #include "mbedtls/ctr_drbg.h"
 #define ENTROPY_NONCE_LEN MBEDTLS_CTR_DRBG_ENTROPY_NONCE_LEN
 
+#if !defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG)
+
 typedef struct
 {
     size_t threshold; /* Minimum bytes to make mbedtls_entropy_func happy */
@@ -118,6 +120,8 @@
                                     MBEDTLS_ENTROPY_SOURCE_STRONG );
 }
 
+#endif /* !defined(MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG) */
+
 /* END_HEADER */
 
 /* BEGIN_DEPENDENCIES
@@ -125,7 +129,7 @@
  * END_DEPENDENCIES
  */
 
-/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_NV_SEED */
+/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_NV_SEED:!MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
 void create_nv_seed( )
 {
     static unsigned char seed[ENTROPY_MIN_NV_SEED_SIZE];
@@ -201,7 +205,7 @@
 }
 /* END_CASE */
 
-/* BEGIN_CASE */
+/* BEGIN_CASE depends_on:!MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
 void custom_entropy_sources( int sources_arg, int expected_init_status_arg )
 {
     psa_status_t expected_init_status = expected_init_status_arg;
@@ -222,7 +226,7 @@
 }
 /* END_CASE */
 
-/* BEGIN_CASE */
+/* BEGIN_CASE depends_on:!MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
 void fake_entropy_source( int threshold,
                           int amount1,
                           int amount2,
@@ -262,7 +266,7 @@
 }
 /* END_CASE */
 
-/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_NV_SEED */
+/* BEGIN_CASE depends_on:MBEDTLS_ENTROPY_NV_SEED:!MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG */
 void entropy_from_nv_seed( int seed_size_arg,
                            int expected_init_status_arg )
 {