diff --git a/library/bignum_core.h b/library/bignum_core.h
index 5a77ef82e2..fc761347ef 100644
--- a/library/bignum_core.h
+++ b/library/bignum_core.h
@@ -70,9 +70,7 @@
 
 #include "common.h"
 
-#if defined(MBEDTLS_BIGNUM_C)
 #include "mbedtls/bignum.h"
-#endif
 
 #include "constant_time_internal.h"