diff --git a/var/spack/repos/builtin/packages/trilinos/package.py b/var/spack/repos/builtin/packages/trilinos/package.py
index c162593ffba..873d383f88a 100644
--- a/var/spack/repos/builtin/packages/trilinos/package.py
+++ b/var/spack/repos/builtin/packages/trilinos/package.py
@@ -232,6 +232,7 @@ class Trilinos(CMakePackage, CudaPackage, ROCmPackage):
         conflicts("+epetraextexperimental")
         conflicts("+epetraextgraphreorderings")
     with when("+teko"):
+        conflicts("~ml")
         conflicts("~stratimikos")
         conflicts("@:12 gotype=long")
     with when("+piro"):