diff --git a/src/api/python/z3/z3.py b/src/api/python/z3/z3.py
index 9f5c22787..f5c5ffb98 100644
--- a/src/api/python/z3/z3.py
+++ b/src/api/python/z3/z3.py
@@ -1107,10 +1107,10 @@ def _coerce_exprs(a, b, ctx=None):
     if not is_expr(a) and not is_expr(b):
         a = _py2expr(a, ctx)
         b = _py2expr(b, ctx)
-    if isinstance(a, str):
-        a = StringVal(a, ctx)
-    if isinstance(b, str):
-        b = StringVal(b, ctx)
+    if isinstance(a, str) and isinstance(b, SeqRef):
+        a = StringVal(a, b.ctx)
+    if isinstance(b, str) and isinstance(a, SeqRef):
+        b = StringVal(b, a.ctx)
     s = None
     s = _coerce_expr_merge(s, a)
     s = _coerce_expr_merge(s, b)