How to handle AX (Keyboard Access & VoiceOver) for AttributedString used in UILabel

I use AttributedString to create a string containing a link. And I set the AttributedString to UILabel. How should I set up the Accessibility feature to make sure that

1. I can keyboard focus on the substring with link and use keyboard operation to open the link
2. I can VoiceOver the whole string and VoiceOver the substring with link to open the link

Thanks a lot.