Regex Omit and Validate

I have this string

"<p></p>" fixed

Is it possible to have a regex that would omit the 7 characters and check if there are at least 3 characters in between?

"<p></p>" = false
"<p>   </p>" = false
"<p>Hello</p>" = true 
"<p>Hello </p>" = true

Further details:-
By default, my editor has the p tags. Therefore my validator is always returning editor string value is not empty. So I want to add the regex expression in the matches fx.

string().required().matches()

>Solution :

I think this is what you look for:

^<p>[\S]{3,}<\/p>$  

if whitespaces are ok for you as well it is this one:

^<p>.{3,}<\/p>$