diff --git a/.gitlab/ci/tests.gitlab-ci.yml b/.gitlab/ci/tests.gitlab-ci.yml
index 8d6423ca57a7995b74b0926bac03a0fc434b1805..00846d546eff071fe4569861353027d737aa7dd2 100644
--- a/.gitlab/ci/tests.gitlab-ci.yml
+++ b/.gitlab/ci/tests.gitlab-ci.yml
@@ -5,10 +5,10 @@ cta_valgrind:
       when: never
     - if: $CI_PIPELINE_SOURCE == "web"
       when: manual
-      allow_failure: false
+      allow_failure: true
     - if: $CI_PIPELINE_SOURCE == "push"
       when: manual
-      allow_failure: false
+      allow_failure: true
     - if: $CI_PIPELINE_SOURCE == "schedule"
       when: on_success
       allow_failure: false
diff --git a/ReleaseNotes.md b/ReleaseNotes.md
index 4398d81f785d88c400f9efa653d6a5736ffc00b4..ec0ff572dc2dd2cc229c1cf587eefb1d4af93e6a 100644
--- a/ReleaseNotes.md
+++ b/ReleaseNotes.md
@@ -15,6 +15,7 @@
 - cta/CTA#238 - Compilation fails when using cta::common::Configuration::getConfEntInt(...)
 ### Continuous Integration
 - cta/CTA#205 - Updating EOS4/EOS4 in versionlock for v4.8.95/v5.1.5
+- cta/CTA#253 - Allow Failure for cta_valgrind tests
 
 # v4.8.1-1