Grafana alerts on Prometheus defined rules

Hi Grafana Community,
I’m using Grafana Open Source v8.3.5 and exploring its alerting capabilities.
After configuring couple of grafana’s managed alerts against a custom webhook and Slack, I can see those are triggered and alerts are received as expected.
However, I was expecting to see all other Prometheus defined rules also alerting using the contact points (or receivers) defined in Grafana, but this is not the case.
In the Alerts page, under the Alert Rules tab I can see the Prometheus rules status (firing, pending), but these rules are not really alerting any of my contact points.

Is there an actual way to integrate those rules into Grafana’s alerts?