diff --git a/tests/psa-client-server/psasim/Makefile b/tests/psa-client-server/psasim/Makefile
index 06d3059b4..b9ec3ad74 100644
--- a/tests/psa-client-server/psasim/Makefile
+++ b/tests/psa-client-server/psasim/Makefile
@@ -24,6 +24,8 @@ PSA_CLIENT_SRC = src/psa_ff_client.c \
 		 src/psa_sim_crypto_client.c \
 		 src/psa_sim_serialise.c
 
+PSA_CLIENT_DEFS = -Isrc -DMBEDTLS_USER_CONFIG_FILE='"psa_sim_client_config_adjust.h"'
+
 PARTITION_SERVER_BOOTSTRAP = src/psa_ff_bootstrap_TEST_PARTITION.c
 
 PSA_SERVER_SRC = $(PARTITION_SERVER_BOOTSTRAP) \
@@ -39,7 +41,7 @@ test/seedfile:
 	dd if=/dev/urandom of=./test/seedfile bs=64 count=1
 
 test/psa_client: $(PSA_CLIENT_SRC) $(GENERATED_H_FILES)
-	$(CC) $(COMMON_INCLUDE) $(CFLAGS) $(PSA_CLIENT_SRC) $(LIBPSACLIENT) $(LDFLAGS) -o $@
+	$(CC) $(COMMON_INCLUDE) $(CFLAGS) $(PSA_CLIENT_DEFS) $(PSA_CLIENT_SRC) $(LIBPSACLIENT) $(LDFLAGS) -o $@
 
 test/psa_partition: $(PSA_SERVER_SRC) $(GENERATED_H_FILES) test/seedfile
 	$(CC) $(COMMON_INCLUDE) $(CFLAGS) $(PSA_SERVER_SRC) $(LIBPSASERVER) $(LDFLAGS) -o $@
diff --git a/tests/psa-client-server/psasim/src/psa_sim_client_config_adjust.h b/tests/psa-client-server/psasim/src/psa_sim_client_config_adjust.h
new file mode 100644
index 000000000..3640c2a2f
--- /dev/null
+++ b/tests/psa-client-server/psasim/src/psa_sim_client_config_adjust.h
@@ -0,0 +1,14 @@
+/**
+ * \file psa_sim_client_config_adjust.h
+ *
+ * \brief User config file for client-side code to be run under PSA simulator
+ */
+
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+
+#define MBEDTLS_PSA_CRYPTO_CLIENT
+#undef MBEDTLS_PSA_CRYPTO_C
+#undef MBEDTLS_PSA_CRYPTO_STORAGE_C