symfony-3.1

I have a problem installing symfony 3.1 in php7, nginx and ubuntu 16.04, i have this error: intl ICU version installed on your system is outdated (55.1) and does not match the ICU data bundled with Symfony (57.1) To get the latest internationalization data upgrade the ICU system package and the intl PHP extension. How can i solve this issue? can i change symfony and use IC 55.1 instead of ICU 57.1? I presume you get this when you run: php bin/symfony_requirements This is just a warning and you can safely ignore the message. I've response to similar questions on this. See this URL for more