diff --git a/tests/psa-client-server/psasim/src/psa_ff_server.c b/tests/psa-client-server/psasim/src/psa_ff_server.c
index b0737ec840..b106092441 100644
--- a/tests/psa-client-server/psasim/src/psa_ff_server.c
+++ b/tests/psa-client-server/psasim/src/psa_ff_server.c
@@ -26,8 +26,6 @@
 #define MAX_CLIENTS 128
 #define MAX_MESSAGES 32
 
-#define SLEEP_US        1
-
 struct connection {
     uint32_t client;
     void *rhandle;
@@ -104,9 +102,6 @@ psa_signal_t psa_wait(psa_signal_t signal_mask, uint32_t timeout)
     uint32_t requested_version;
     ssize_t len;
     int idx;
-#if !defined(PSASIM_USE_USLEEP)
-    const struct timespec ts_delay = { .tv_sec = 0, .tv_nsec = SLEEP_US * 1000 };
-#endif
 
     if (timeout == PSA_POLL) {
         INFO("psa_wait: Called in polling mode");
@@ -261,11 +256,6 @@ psa_signal_t psa_wait(psa_signal_t signal_mask, uint32_t timeout)
             break;
         } else {
             /* There is no 'select' function in SysV to block on multiple queues, so busy-wait :( */
-#if defined(PSASIM_USE_USLEEP)
-            usleep(SLEEP_US);
-#else /* PSASIM_USE_USLEEP */
-            nanosleep(&ts_delay, NULL);
-#endif /* PSASIM_USE_USLEEP */
         }
     } while (timeout == PSA_BLOCK);