diff --git a/portable/IAR/ARM_CM0/portmacro.h b/portable/IAR/ARM_CM0/portmacro.h
index 66c26d73a..b38e69b64 100644
--- a/portable/IAR/ARM_CM0/portmacro.h
+++ b/portable/IAR/ARM_CM0/portmacro.h
@@ -78,7 +78,6 @@
 /* Scheduler utilities. */
     extern void vPortYield( void );
     #define portNVIC_INT_CTRL                           ( ( volatile uint32_t * ) 0xe000ed04 )
-    #define portNVIC_INT_CTRL_REG                       ( *( portNVIC_INT_CTRL ) )
     #define portNVIC_PENDSVSET                          0x10000000
     #define portYIELD()                                 vPortYield()
     #define portEND_SWITCHING_ISR( xSwitchRequired )    if( xSwitchRequired ) *( portNVIC_INT_CTRL ) = portNVIC_PENDSVSET