Ubuntu :: Error: Allowed Memory Size Of 20971520 Bytes Exhausted (tried To Allocate 7680 Bytes) In /var/www/index.php On Line 2

I recently had to move to a new machine, everything went well except for one thing. I did fresh installation of LAMP server all with default configs. Every time I'm using PHP script to that invokes include, require or require_once I get the following error:

Code: Fatal error: Allowed memory size of 20971520 bytes exhausted (tried to allocate 7680 bytes) in /var/www/index.php on line 2 index.php file: PHP Code:
<?php    include "index.php";?>
icukapi.php file:
PHP Code:
<?php    echo "test";?>

My memory_limit in php.ini is set to 20M. I tried to increase that however it didn't quite work. PHP seems to allocate all possible space and return that message every time i try. If somebody has an idea of how to fix it I would be more than grateful. I spend quite a long time searching for an answer however the all things i found suggested increating memory_limit which in this case doesn't work.