diff --git a/.readthedocs.yaml b/.readthedocs.yaml
new file mode 100644
index 0000000000..98ca8b581d
--- /dev/null
+++ b/.readthedocs.yaml
@@ -0,0 +1,13 @@
+version: 2
+
+build:
+  os: "ubuntu-20.04"
+  tools:
+    python: "3.9"
+
+sphinx:
+  configuration: docs/source/conf.py
+
+python:
+  install:
+    - requirements: docs/requirements-rtd.txt
diff --git a/docs/requirements-rtd.txt b/docs/requirements-rtd.txt
index bf75537a88..c3d1c0372b 100644
--- a/docs/requirements-rtd.txt
+++ b/docs/requirements-rtd.txt
@@ -1,3 +1,4 @@
+sphinx==4.3.0
 sphinx-numfig
 jupyter
 sphinxcontrib-katex