Regex for validating multiple E-Mail-Addresses

I got a Regex that validates my mail-addresses like this:

([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)

This works perfectly fine, but only allows one e-mail to be entered. Now I wanted to extend that and allow multiple mail-addresses to be added (just like MS Outlook, for example) with a semicolon as a mail-splitter.

mail1@tld.com;mail2@tld.com;mail3@tld.com

Now I've searched and found this one:

([A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,4}(;|$))

This works on one point, but sadly requires a semicolon at the end of a mail:

mail1@tld.com;

This is not what I want when the user only enters one e-mail.

How can I extend my regex above (the first one) to allow multiple mail-addresses to be added while let them be splitted through a semicolon?