php - Unexpected T_Variable with SimpleXML -

i mistake

parse error: syntax error, unexpected '$xml2' (t_variable) in /users/craftamap/www/craft_cms/index.php on line 4 

by using code.

if (file_exists("xml/sites.xml")) {     $xml2 = simplexml_load_file("xml/sites.xml"); } 

i can't figure out mistake. file existing.

thank help.