diff --git a/packaging/_parser.py b/packaging/_parser.py
index d03119a1..4dcf03d1 100644
--- a/packaging/_parser.py
+++ b/packaging/_parser.py
@@ -197,11 +197,13 @@ def _parse_extras_list(tokenizer: Tokenizer) -> List[str]:
 
 def _parse_specifier(tokenizer: Tokenizer) -> str:
     """
-    specifier = LEFT_PARENTHESIS version_many RIGHT_PARENTHESIS
-              | version_many
+    specifier = LEFT_PARENTHESIS WS? version_many WS? RIGHT_PARENTHESIS
+              | WS? version_many WS?
     """
     with tokenizer.enclosing_tokens("LEFT_PARENTHESIS", "RIGHT_PARENTHESIS"):
+        tokenizer.consume("WS")
         parsed_specifiers = _parse_version_many(tokenizer)
+        tokenizer.consume("WS")
 
     return parsed_specifiers
 
diff --git a/tests/test_requirements.py b/tests/test_requirements.py
index 92cf9ce6..36ea474b 100644
--- a/tests/test_requirements.py
+++ b/tests/test_requirements.py
@@ -79,9 +79,9 @@
         ("git+https://git.example.com/MyProject.git@v1.0", ""),
         ("git+https://git.example.com/MyProject.git@refs/pull/123/head", ""),
         (None, "==={ws}arbitrarystring"),
-        (None, "(==={ws}arbitrarystring)"),
+        (None, "({ws}==={ws}arbitrarystring{ws})"),
         (None, "=={ws}1.0"),
-        (None, "(=={ws}1.0)"),
+        (None, "({ws}=={ws}1.0{ws})"),
         (None, "<={ws}1!3.0.0.rc2"),
         (None, ">{ws}2.2{ws},{ws}<{ws}3"),
         (None, "(>{ws}2.2{ws},{ws}<{ws}3)"),