diff --git a/src/Makevars b/src/Makevars
index 5aec758..e9b4228 100644
--- a/src/Makevars
+++ b/src/Makevars
@@ -1,4 +1,3 @@
 PKG_CPPFLAGS = -I../inst/include/
-CXX_STD = CXX11
 PKG_LIBS = $(SHLIB_OPENMP_CXXFLAGS) $(LAPACK_LIBS) $(BLAS_LIBS) $(FLIBS)
 PKG_CXXFLAGS = $(SHLIB_OPENMP_CXXFLAGS)
diff --git a/src/Makevars.win b/src/Makevars.win
index 5aec758..e9b4228 100644
--- a/src/Makevars.win
+++ b/src/Makevars.win
@@ -1,4 +1,3 @@
 PKG_CPPFLAGS = -I../inst/include/
-CXX_STD = CXX11
 PKG_LIBS = $(SHLIB_OPENMP_CXXFLAGS) $(LAPACK_LIBS) $(BLAS_LIBS) $(FLIBS)
 PKG_CXXFLAGS = $(SHLIB_OPENMP_CXXFLAGS)