Error when deleting partner event source in aws EventBridge

This is a two step process to delete the partner event source/event bus which got created by Salesforce Event relay.

1. First step to login to salesforce account-->Go to Setup-->Search for "EVENT RELAYS" and click on it--> select the Event Relay corresponding to your partner event bus name --> click Delete (After Event Relay deleted in Salesforce account, your Partner event source gets deleted in your AWS account)
2. Second step to delete the associated partner event bus and Rule from the "Event Buses" page of Amazon Event Bridge console

Please approve and like my answer if you find it helps you in anyway.

Thanks

We cannot remove it as it is an API used by SaaS partners as described in the documentation below.
https://awscli.amazonaws.com/v2/documentation/api/latest/reference/events/delete-partner-event-source.html

This operation is used by SaaS partners to delete a partner event source. This operation is not used by Amazon Web Services customers.

When you delete an event source, the status of the corresponding partner event bus in the Amazon Web Services customer account becomes DELETED.

I believe that to disconnect from salesforce, you would need to delete the settings on the salesforce side.
Then delete the associated EventBridge event rule.
Delete the event bus that was used in the event rules.