diff --git a/babel/messages/pofile.py b/babel/messages/pofile.py
index e3b99e4b6..b002d2b1f 100644
--- a/babel/messages/pofile.py
+++ b/babel/messages/pofile.py
@@ -174,6 +174,8 @@ def __init__(
         self.counter = 0
         self.offset = 0
         self.abort_invalid = abort_invalid
+        # Identical message IDs share one string object while parsing.
+        self._msgids: dict[str, str] = {}
         self._reset_message_state()
 
     def _reset_message_state(self) -> None:
@@ -210,6 +212,10 @@ def _add_message(self) -> None:
         else:
             msgid = self.messages[0].denormalize()
             string = self.translations[0][1].denormalize()
+        if isinstance(msgid, tuple):
+            msgid = tuple(self._msgids.setdefault(part, part) for part in msgid)
+        else:
+            msgid = self._msgids.setdefault(msgid, msgid)
         msgctxt = self.context.denormalize() if self.context else None
         message = Message(
             msgid,
diff --git a/tests/messages/test_pofile_read.py b/tests/messages/test_pofile_read.py
index d17f5d4af..973d78ba1 100644
--- a/tests/messages/test_pofile_read.py
+++ b/tests/messages/test_pofile_read.py
@@ -406,6 +406,36 @@ def test_with_context_two():
     assert out_buf.getvalue().strip() == buf.getvalue().strip(), out_buf.getvalue()
 
 
+def test_repeated_msgids_share_strings():
+    buf = StringIO(r'''msgctxt "Menu"
+msgid "Open"
+msgstr "Ouvrir"
+
+msgctxt "Button"
+msgid "Open"
+msgstr "Ouvrir"
+
+msgctxt "Menu"
+msgid "%d file"
+msgid_plural "%d files"
+msgstr[0] "%d fichier"
+msgstr[1] "%d fichiers"
+
+msgctxt "Button"
+msgid "%d file"
+msgid_plural "%d files"
+msgstr[0] "%d fichier"
+msgstr[1] "%d fichiers"
+''')
+    catalog = pofile.read_po(buf)
+    assert catalog.get('Open', context='Menu').id is catalog.get('Open', context='Button').id
+    menu_id = catalog.get('%d file', context='Menu').id
+    button_id = catalog.get('%d file', context='Button').id
+    assert menu_id == button_id == ('%d file', '%d files')
+    assert menu_id[0] is button_id[0]
+    assert menu_id[1] is button_id[1]
+
+
 def test_single_plural_form():
     buf = StringIO(r'''msgid "foo"
 msgid_plural "foos"