Run method before suite in TestNG via XML

I have an XML TestNG suite:

<suite name="mySuite" parallel="classes" thread-count="5">
    <test name="myTest">
        <packages>
            <package name="mypack.*"/>
        </packages>
    </test>
</suite>

and I'd like to run a method every time before the suite.

Is it possible to have something like this:

<suite name="mySuite" parallel="classes" thread-count="5">
    <before-suite>...</before-suite> <!-- Here I want to run a single method  -->
    <test name="myTest">
        <packages>
            <package name="mypack.*"/>
        </packages>
    </test>
</suite>

?