diff --git a/README.md b/README.md
index 3fc4859b8637f6eb85d14b9a3335af9f0055d2fd..36c3bcdf79d4a7fd8a549c1fabca0f51bebab0c4 100644
--- a/README.md
+++ b/README.md
@@ -10,7 +10,7 @@ This version is known to compile with:
  - A development version of [GPFSL].
 
 The easiest way to install the correct versions of the dependencies is through
-opam (1.2.2 or newer).  You will need the Coq and Iris opam repositories:
+opam (2.0.0 or newer).  You will need the Coq and Iris opam repositories:
 
     opam repo add coq-released https://coq.inria.fr/opam/released
     opam repo add iris-dev https://gitlab.mpi-sws.org/iris/opam.git