diff --git a/platform/mbed_wait_api_rtos.cpp b/platform/mbed_wait_api_rtos.cpp
index b535937840..f24f58cbdd 100644
--- a/platform/mbed_wait_api_rtos.cpp
+++ b/platform/mbed_wait_api_rtos.cpp
@@ -39,11 +39,10 @@ void wait_us(int us)
     const ticker_data_t *const ticker = get_us_ticker_data();
 
     uint32_t start = ticker_read(ticker);
-    // Use the RTOS to wait for millisecond delays if possible
-    int ms = us / 1000;
-    if ((ms > 0) && core_util_are_interrupts_enabled()) {
+    if ((us >= 1000) && core_util_are_interrupts_enabled()) {
+        // Use the RTOS to wait for millisecond delays if possible
         sleep_manager_lock_deep_sleep();
-        Thread::wait((uint32_t)ms);
+        Thread::wait((uint32_t)us / 1000);
         sleep_manager_unlock_deep_sleep();
     }
     // Use busy waiting for sub-millisecond delays, or for the whole