diff --git a/nfapi/oai_integration/nfapi_pnf.c b/nfapi/oai_integration/nfapi_pnf.c
index 2b5d7fcfe2..1aa0c50a81 100644
--- a/nfapi/oai_integration/nfapi_pnf.c
+++ b/nfapi/oai_integration/nfapi_pnf.c
@@ -2258,8 +2258,32 @@ void oai_subframe_ind(uint16_t sfn, uint16_t sf) {
   }
 }
 
+#define SLOT_DURATION 300  // in microseconds
+static void maybe_slow_down_pnf(void)
+{
+  /* uses a usleep to wait for approximately the same time period (300 us) */
+  static struct timespec last_execution = {0};
+  struct timespec current_execution;
+  clock_gettime(CLOCK_REALTIME, &current_execution);
+  // Calculate elapsed time since last execution
+  long elapsed_time = (current_execution.tv_sec - last_execution.tv_sec) * 1000000; // Convert seconds to microseconds
+  elapsed_time += (current_execution.tv_nsec - last_execution.tv_nsec) / 1000; // Convert nanoseconds to microseconds
+  if (elapsed_time < SLOT_DURATION)
+    usleep(SLOT_DURATION - elapsed_time);
+  // Update last_execution time
+  last_execution = current_execution;
+}
+
 void handle_nr_slot_ind(uint16_t sfn, uint16_t slot)
 {
+  if (IS_SOFTMODEM_RFSIM) {
+    // RFsim can run faster than realtime. However, we need to give the VNF
+    // some time to send an answer, so the PNF can run faster than realtime,
+    // but it should not too much. This function will "maybe" slow down, up to
+    // a slot length of SLOT_DURATION us
+    maybe_slow_down_pnf();
+  }
+    
     //send VNF slot indication, which is aligned with TX thread, so that it can call the scheduler
     //we give four additional slots (2ms) which should be enough time for the VNF to
     //answer