diff --git a/.pre-commit-hooks.yaml b/.pre-commit-hooks.yaml
index 8aa5c4ec..1a89f9ec 100644
--- a/.pre-commit-hooks.yaml
+++ b/.pre-commit-hooks.yaml
@@ -32,3 +32,10 @@
   pass_filenames: false
   language: python
   files: (__manifest__\.py|__openerp__\.py|__terp__\.py)$
+
+- id: oca-gen-external-dependencies
+  name: Generate requirements.txt for an addons directory
+  entry: oca-gen-external-dependencies
+  language: python
+  pass_filenames: false
+  files: (__manifest__\.py|__openerp__\.py|__terp__\.py|setup\.py|pyproject\.toml)$
diff --git a/setup.py b/setup.py
index c7136fa3..929a8ee5 100644
--- a/setup.py
+++ b/setup.py
@@ -41,6 +41,9 @@
         "selenium",
         "twine",
         "wheel",
+        "pyproject_dependencies ; python_version>='3.7'",
+        "setuptools-odoo",  # for oca-gen-external-dependencies
+        "whool",  # for oca-gen-external-dependencies
     ],
     python_requires=">=3.6",
     classifiers=[
@@ -67,6 +70,7 @@
             "oca-publish-modules = tools.publish_modules:main",
             "oca-gen-addon-readme = tools.gen_addon_readme:gen_addon_readme",
             "oca-gen-addon-icon = tools.gen_addon_icon:gen_addon_icon",
+            "oca-gen-external-dependencies = tools.gen_external_dependencies:main",
             "oca-gen-metapackage = tools.gen_metapackage:main",
             "oca-towncrier = tools.oca_towncrier:oca_towncrier",
             "oca-create-migration-issue = tools.create_migration_issue:main",
diff --git a/tests/test_gen_external_dependencies.py b/tests/test_gen_external_dependencies.py
new file mode 100644
index 00000000..591bb8ec
--- /dev/null
+++ b/tests/test_gen_external_dependencies.py
@@ -0,0 +1,65 @@
+import subprocess
+import sys
+import textwrap
+
+import pytest
+
+from tools.gen_external_dependencies import main as gen_external_dependencies
+
+from .utils import dir_changer
+
+
+def _make_addon(
+    addons_dir, addon_name, depends, external_dependencies, installable=True
+):
+    addon_dir = addons_dir / addon_name
+    addon_dir.mkdir()
+    manifest = {
+        "name": addon_name,
+        "version": "16.0.1.0.0",
+        "depends": depends,
+        "external_dependencies": external_dependencies,
+        "installable": installable,
+    }
+    addon_dir.joinpath("__manifest__.py").write_text(repr(manifest))
+    addon_dir.joinpath("__init__.py").touch()
+
+
+@pytest.mark.skipif("sys.version_info < (3,7)")
+def test_gen_external_dependencies(tmp_path):
+    ...
+    _make_addon(
+        tmp_path,
+        addon_name="addon1",
+        depends=["mis_builder"],
+        external_dependencies={"python": ["requests", "xlrd"]},
+    )
+    _make_addon(
+        tmp_path,
+        addon_name="addon2",
+        depends=[],
+        external_dependencies={"python": ["requests", "pydantic>=2"]},
+    )
+    _make_addon(
+        tmp_path,
+        addon_name="addon3",
+        depends=[],
+        external_dependencies={},
+        installable=False,
+    )
+    with dir_changer(tmp_path):
+        assert gen_external_dependencies() != 0  # no pyproject.toml
+        subprocess.run([sys.executable, "-m", "whool", "init"], check=True)
+        assert tmp_path.joinpath("addon1").joinpath("pyproject.toml").is_file()
+        assert tmp_path.joinpath("addon2").joinpath("pyproject.toml").is_file()
+        assert gen_external_dependencies() == 0
+        requirements_txt_path = tmp_path.joinpath("requirements.txt")
+        assert requirements_txt_path.is_file()
+        assert requirements_txt_path.read_text() == textwrap.dedent(
+            """\
+            # generated from manifests external_dependencies
+            pydantic>=2
+            requests
+            xlrd
+            """
+        )
diff --git a/tools/gen_external_dependencies.py b/tools/gen_external_dependencies.py
new file mode 100644
index 00000000..7de81d0d
--- /dev/null
+++ b/tools/gen_external_dependencies.py
@@ -0,0 +1,66 @@
+#!/usr/bin/env python3
+"""Generate requirements.txt with external dependencies of Odoo addons."""
+
+import os
+import subprocess
+import sys
+from pathlib import Path
+
+
+def main() -> int:
+    if sys.version_info < (3, 7):
+        raise SystemExit("Python 3.7+ is required.")
+
+    projects = [
+        *Path.glob(Path.cwd(), "*/pyproject.toml"),
+        *Path.glob(Path.cwd(), "setup/*/setup.py"),
+    ]
+
+    if not projects:
+        return 1
+
+    env = os.environ.copy()
+    env.update(
+        {
+            # for better performance, since we are not interested in precise versions
+            "WHOOL_POST_VERSION_STRATEGY_OVERRIDE": "none",
+            "SETUPTOOLS_ODOO_POST_VERSION_STRATEGY_OVERRIDE": "none",
+        }
+    )
+
+    result = subprocess.run(
+        [
+            sys.executable,
+            "-m",
+            "pyproject_dependencies",
+            "--no-isolation",  # whool and setuptools Odoo must be preinstalled
+            "--ignore-build-errors",  # ignore uninstallable addons
+            "--name-filter",
+            r"^(odoo$|odoo\d*-addon-)",  # filter out odoo and odoo addons
+            *projects,
+        ],
+        env=env,
+        check=False,
+        stdout=subprocess.PIPE,
+        text=True,
+    )
+
+    if result.returncode != 0:
+        return result.returncode
+
+    requirements = result.stdout
+
+    requirements_path = Path("requirements.txt")
+    if requirements:
+        with requirements_path.open("w") as f:
+            f.write("# generated from manifests external_dependencies\n")
+            f.write(requirements)
+    else:
+        if requirements_path.exists():
+            requirements_path.unlink()
+
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())