diff --git a/pyproject.toml b/pyproject.toml
index 3b25e46317..72c2df7e17 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -2,14 +2,5 @@
 requires = [
     "setuptools",
     "wheel",
-    "numpy==1.13.3; python_version=='2.7' and platform_system!='AIX'",
-    "numpy==1.13.3; python_version=='3.5' and platform_system!='AIX'",
-    "numpy==1.13.3; python_version=='3.6' and platform_system!='AIX'",
-    "numpy==1.14.5; python_version=='3.7' and platform_system!='AIX'",
-    "numpy==1.17.3; python_version>='3.8' and platform_system!='AIX'",
-    "numpy==1.16.0; python_version=='2.7' and platform_system=='AIX'",
-    "numpy==1.16.0; python_version=='3.5' and platform_system=='AIX'",
-    "numpy==1.16.0; python_version=='3.6' and platform_system=='AIX'",
-    "numpy==1.16.0; python_version=='3.7' and platform_system=='AIX'",
-    "numpy==1.17.3; python_version>='3.8' and platform_system=='AIX'",
+    "oldest-supported-numpy"
 ]
diff --git a/setup.py b/setup.py
index 4911777e89..37b689786e 100644
--- a/setup.py
+++ b/setup.py
@@ -216,6 +216,7 @@ def get_long_description():
     cmdclass=cmdclass,
     setup_requires=["numpy"],
     ext_modules=prepare_modules(),
+    python_requires=">=3.6",
     zip_safe=False,
 )