diff --git a/jsonnet/kube-prometheus/components/prometheus.libsonnet b/jsonnet/kube-prometheus/components/prometheus.libsonnet
index e93f8537..63d6d061 100644
--- a/jsonnet/kube-prometheus/components/prometheus.libsonnet
+++ b/jsonnet/kube-prometheus/components/prometheus.libsonnet
@@ -251,6 +251,7 @@ function(params) {
           namespace: p.config.namespace,
           name: 'alertmanager-' + p.config.alertmanagerName,
           port: 'web',
+          apiVersion: 'v2',
         }],
       },
       securityContext: {
diff --git a/manifests/prometheus-prometheus.yaml b/manifests/prometheus-prometheus.yaml
index 36fd374f..f1f8ef2f 100644
--- a/manifests/prometheus-prometheus.yaml
+++ b/manifests/prometheus-prometheus.yaml
@@ -12,7 +12,8 @@ metadata:
 spec:
   alerting:
     alertmanagers:
-    - name: alertmanager-main
+    - apiVersion: v2
+      name: alertmanager-main
       namespace: monitoring
       port: web
   image: quay.io/prometheus/prometheus:v2.24.0