diff --git a/src/include/netif/ppp/ppp_impl.h b/src/include/netif/ppp/ppp_impl.h
index 56a29a54..b149c132 100644
--- a/src/include/netif/ppp/ppp_impl.h
+++ b/src/include/netif/ppp/ppp_impl.h
@@ -81,6 +81,12 @@ extern "C" {
 #define	PPP_ESCAPE	0x7d	/* Asynchronous Control Escape */
 #define	PPP_TRANS	0x20	/* Asynchronous transparency modifier */
 
+/*
+ * PPP_DEFMRU: MRU value used prior negotiation and unless negotiated later.
+ * Must be 1500.
+ */
+#define PPP_DEFMRU      1500
+
 /*
  * Protocol field values.
  */
diff --git a/src/include/netif/ppp/ppp_opts.h b/src/include/netif/ppp/ppp_opts.h
index dfe988cc..8fe4a3ee 100644
--- a/src/include/netif/ppp/ppp_opts.h
+++ b/src/include/netif/ppp/ppp_opts.h
@@ -501,13 +501,6 @@
 #define PPP_MRU                         1500
 #endif
 
-/**
- * PPP_DEFMRU: Default MRU to try
- */
-#ifndef PPP_DEFMRU
-#define PPP_DEFMRU                      1500
-#endif
-
 /**
  * PPP_MAXMRU: Normally limit MRU to this (pppd default = 16384)
  */