diff --git a/CHANGELOG.md b/CHANGELOG.md
index cc278a74..70a52bfb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- CLI: fix accepting keyword arguments ([#420](https://github.com/Lightning-AI/utilities/pull/420))
 - Scripts: fix CLI parsing ([#419](https://github.com/Lightning-AI/utilities/pull/419))
 
 
diff --git a/src/lightning_utilities/cli/__main__.py b/src/lightning_utilities/cli/__main__.py
index 7beb2991..47ceb6f5 100644
--- a/src/lightning_utilities/cli/__main__.py
+++ b/src/lightning_utilities/cli/__main__.py
@@ -21,15 +21,18 @@ def main() -> None:
     from jsonargparse import auto_cli, set_parsing_settings
 
     set_parsing_settings(parse_optionals_as_positionals=True)
-    auto_cli({
-        "requirements": {
-            "_help": "Manage requirements files.",
-            "prune-pkgs": prune_packages_in_requirements,
-            "set-oldest": replace_oldest_version,
-            "replace-pkg": replace_package_in_requirements,
+    auto_cli(
+        {
+            "requirements": {
+                "_help": "Manage requirements files.",
+                "prune-pkgs": prune_packages_in_requirements,
+                "set-oldest": replace_oldest_version,
+                "replace-pkg": replace_package_in_requirements,
+            },
+            "version": _get_version,
         },
-        "version": _get_version,
-    })
+        as_positional=False,
+    )
 
 
 if __name__ == "__main__":
diff --git a/tests/unittests/cli/test_command_line.py b/tests/unittests/cli/test_command_line.py
new file mode 100644
index 00000000..a379adf5
--- /dev/null
+++ b/tests/unittests/cli/test_command_line.py
@@ -0,0 +1,66 @@
+import subprocess
+from pathlib import Path
+
+import pytest
+
+
+def test_version():
+    """Prints the help message for the requirements commands."""
+    return_code = subprocess.call(["python", "-mlightning_utilities.cli", "version"])  # noqa: S607
+    assert return_code == 0
+
+
+@pytest.mark.parametrize("args", ["positional", "optional"])
+class TestRequirements:
+    """Test requirements commands."""
+
+    BASE_CMD = ("python", "-m", "lightning_utilities.cli", "requirements")
+    REQUIREMENTS_SAMPLE = """
+# This is sample requirements file
+#  with multi line comments
+
+torchvision >=0.13.0, <0.16.0  # sample # comment
+gym[classic,control] >=0.17.0, <0.27.0
+ipython[all] <8.15.0  # strict
+torchmetrics >=0.10.0, <1.3.0
+deepspeed >=0.8.2, <=0.9.3; platform_system != "Windows"  # strict
+    """
+
+    def _create_requirements_file(self, local_path: Path, filename: str = "testing-cli-requirements.txt"):
+        """Create a sample requirements file."""
+        req_file = local_path / filename
+        with open(req_file, "w", encoding="utf8") as fopen:
+            fopen.write(self.REQUIREMENTS_SAMPLE)
+        return str(req_file)
+
+    def _build_command(self, subcommand: str, cli_params: tuple, arg_style: str):
+        """Build the command for the CLI."""
+        if arg_style == "positional":
+            return list(self.BASE_CMD) + [subcommand] + [value for _, value in cli_params]
+        if arg_style == "optional":
+            return list(self.BASE_CMD) + [subcommand] + [f"--{key}={value}" for key, value in cli_params]
+        raise ValueError(f"Unknown test configuration: {arg_style}")
+
+    def test_requirements_prune_pkgs(self, args, tmp_path):
+        """Prune packages from requirements files."""
+        req_file = self._create_requirements_file(tmp_path)
+        cli_params = (("packages", "ipython"), ("req_files", req_file))
+        cmd = self._build_command("prune-pkgs", cli_params, args)
+        return_code = subprocess.call(cmd)  # noqa: S603
+        assert return_code == 0
+
+    def test_requirements_set_oldest(self, args, tmp_path):
+        """Set the oldest version of packages in requirement files."""
+        req_file = self._create_requirements_file(tmp_path, "requirements.txt")
+        cli_params = (("req_files", req_file),)
+        cmd = self._build_command("set-oldest", cli_params, args)
+        return_code = subprocess.call(cmd)  # noqa: S603
+        assert return_code == 0
+
+    def test_requirements_replace_pkg(self, args, tmp_path):
+        """Replace a package in requirements files."""
+        req_file = self._create_requirements_file(tmp_path, "requirements.txt")
+        cli_params = (("old_package", "torchvision"), ("new_package", "torchtext"), ("req_files", req_file))
+        cmd = self._build_command("replace-pkg", cli_params, args)
+        return_code = subprocess.call(cmd)  # noqa: S603
+        assert return_code == 0