How to restrict Contract Access by Party Tab within a BU

Summary:

I would like to enable a full access of a contract only the users shown on parties tab.

In other words, I would to prevent the full access for those users not included in the party tab.

The users are under the only one BU.

How can I implement this requirement?

Content (please ensure you mask any confidential information):

Version (include the version you are using, if applicable):

24D

Code Snippet (add any code snippets that support your topic, if applicable):