diff --git a/src/parallel/decompose/ptscotchDecomp/Make/options b/src/parallel/decompose/ptscotchDecomp/Make/options
index b2b76fce05..488f5ef3bb 100644
--- a/src/parallel/decompose/ptscotchDecomp/Make/options
+++ b/src/parallel/decompose/ptscotchDecomp/Make/options
@@ -8,4 +8,4 @@ EXE_INC = \
     -I../decompositionMethods/lnInclude
 
 LIB_LIBS = \
-    -L$(FOAM_MPI_LIBBIN) -lptscotch -lptscotcherrexit
+    -L$(FOAM_MPI_LIBBIN) -lptscotch -lptscotcherrexit -lrt
diff --git a/src/parallel/decompose/scotchDecomp/Make/options b/src/parallel/decompose/scotchDecomp/Make/options
index 96b64b8fdd..2f01188ac6 100644
--- a/src/parallel/decompose/scotchDecomp/Make/options
+++ b/src/parallel/decompose/scotchDecomp/Make/options
@@ -4,4 +4,4 @@ EXE_INC = \
     -I../decompositionMethods/lnInclude
 
 LIB_LIBS = \
-    -lscotch -lscotcherrexit
+    -lscotch -lscotcherrexit -lrt