如何加载yml文件而不是xliff来翻译Symfony项目

I deleted the file messages.fr.xlf and I replaced it by messages.fr.yml.

I got this Exception.

An exception has been thrown during the rendering of a template ("Unable to load "/home/mkubik/myproject/src/tuto/UserBundle/Resources/translations/messages.fr.xlf": File /home/mkubik/myproject/src/tuto/UserBundle/Resources/translations/messages.fr.xlf does not contain valid XML, it is empty.") in tutoBlogBundle:Blog:traduction.html.twig at line 3.

I have cleared the cache.

He continue to load the xlf file, but I do not know where ..

There is my template traduction.html.twig :

<html>
<body>
    {{ 'hello'|trans({'%name%': name}) }}
        {% for i in 0..2 %}
            <p>{{ ('charte.donnee.' ~ i )|trans }}</p>
        {% endfor %}
    {{ 'article.nombre'|transchoice(2) }}
    Aujourd'hui nous somme le {{ 'now'|localizeddate('full', 'none') }} et il est {{ 'now'|localizeddate('none', 'short') }}
</body>
</html>

Do you have an idea please, thanks !!