diff --git a/configure.ac b/configure.ac
index f9f0faf..515cdf1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -289,6 +289,11 @@ if (test "${enable_external_ell}" = "yes"); then
 	AC_SUBST(ELL_CFLAGS)
 	AC_SUBST(ELL_LIBS)
 fi
+if (test "${enable_external_ell}" != "yes"); then
+	AC_CHECK_FILE(${srcdir}/ell/ell.h, dummy=yes,
+			AC_CHECK_FILE(${srcdir}/../ell/ell/ell.h, dummy=yes,
+				AC_MSG_ERROR(ELL source is required or use --enable-external-ell)))
+fi
 AM_CONDITIONAL(EXTERNAL_ELL, test "${enable_external_ell}" = "yes" ||
 				(test "${enable_btpclient}" != "yes" &&
 						test "${enable_mesh}" != "yes"))