diff --git a/pystencils/astnodes.py b/pystencils/astnodes.py
index eb5910f9c5a7aa9a990d25d681e45e63a34188f4..05106e36595e6c6fe9aa64ea60b4b2661a4d688b 100644
--- a/pystencils/astnodes.py
+++ b/pystencils/astnodes.py
@@ -503,7 +503,7 @@ class SympyAssignment(Node):
     def __init__(self, lhs_symbol, rhs_expr, is_const=True):
         super(SympyAssignment, self).__init__(parent=None)
         self._lhs_symbol = lhs_symbol
-        self.rhs = sp.simplify(rhs_expr)
+        self.rhs = sp.sympify(rhs_expr)
         self._is_const = is_const
         self._is_declaration = self.__is_declaration()