diff --git a/xarray/core/groupby.py b/xarray/core/groupby.py
index 2a75c35c255..1d2f62cfff7 100644
--- a/xarray/core/groupby.py
+++ b/xarray/core/groupby.py
@@ -587,9 +587,7 @@ def groups(self) -> dict[GroupKey, GroupIndex]:
         """
         # provided to mimic pandas.groupby
         if self._groups is None:
-            self._raise_if_not_single_group()
-            (grouper,) = self.groupers
-            self._groups = dict(zip(grouper.unique_coord.values, self._group_indices))
+            self._groups = dict(zip(self._unique_coord.data, self._group_indices))
         return self._groups
 
     def __getitem__(self, key: GroupKey) -> T_Xarray: