diff --git a/libraries/mbed/common/us_ticker_api.c b/libraries/mbed/common/us_ticker_api.c
index f98b56a9e8..716e78103a 100644
--- a/libraries/mbed/common/us_ticker_api.c
+++ b/libraries/mbed/common/us_ticker_api.c
@@ -117,6 +117,16 @@ void us_ticker_remove_event(ticker_event_t *obj) {
     __enable_irq();
 }
 
-timestamp_t us_ticker_get_next_timestamp(void) {
-    return head->timestamp;
+int us_ticker_get_next_timestamp(timestamp_t *timestamp) {
+    int ret = 0;
+
+    /* if head is NULL, there are no pending events */
+    __disable_irq();
+    if (head != NULL) {
+        *timestamp = head->timestamp;
+        ret = 1;
+    }
+    __enable_irq();
+
+    return ret;
 }
diff --git a/libraries/mbed/hal/us_ticker_api.h b/libraries/mbed/hal/us_ticker_api.h
index 543c4da934..1fa93170ec 100644
--- a/libraries/mbed/hal/us_ticker_api.h
+++ b/libraries/mbed/hal/us_ticker_api.h
@@ -43,7 +43,7 @@ void us_ticker_irq_handler(void);
 
 void us_ticker_insert_event(ticker_event_t *obj, timestamp_t timestamp, uint32_t id);
 void us_ticker_remove_event(ticker_event_t *obj);
-timestamp_t us_ticker_get_next_timestamp(void);
+int us_ticker_get_next_timestamp(timestamp_t *timestamp);
 
 #ifdef __cplusplus
 }