Access a file from other domain/server

I tried this piece of code:

RewriteEngine ON
RewriteRule ^aboutus.html$ http://www.domain1.com/about_us.php [P]

Its working, but for few files i use secured connection.

If i use

RewriteRule ^aboutus.html$ http://www.domain1.aboutus.php [P]

it is works perfectly

But

RewriteRule ^aboutus.html$ https://www.domain1.aboutus.php [P]

It gives an internal server error.