i need to split xml using xpath in perl

i have a input xml which i have to split based on doc and delt wise and save it in this format delt_0001.xml i want this xml to split using xpath in perl

input xml delt.xml

<xml>
<service>
<title>split xml</title>
<main>
<doc id=001>
<title>doc1</title>
<delt id=0001>
<title>delt1</title>
<text>num1</text>``
<text>num1</text>
<delt>
<delt id=0002-A>
<title>delt1</title>
<text>num1</text>
<text>num1</text>
<delt>
</doc>
<doc id=002>
<title>doc2</title>
<delt id=0003>
<title>delt1</title>
<text>num1</text>
<text>num1</text>
<delt>
<delt id=0004>
<title>delt1</title>
<text>num1</text>
<text>num1</text>
<delt>
</doc>
</main>
</service>
</xml>

output needed The output has to be saved based on delt id for eg: delt_0001.xml

split no 1 delt_0001.xml
<xml>
<service>
<title>split xml</title>
<main>
<doc id=001>
<title>doc1</title>
<delt id=0001>
<title>delt1</title>
<text>num1</text>``
<text>num1</text>
</delt>
</doc>
</main>
</service>
</xml>



split no 2 delt_0002-A.xml
<xml>
<service>
<title>split xml</title>
<main>
<doc id=001>
<title>doc1</title>
<delt id=0002=A>
<title>delt1</title>
<text>num1</text>
<text>num1</text>
</delt>
</doc>
</main>
</service>
</xml>


split no 3 delt_0003.xml
<xml>
<service>
<title>split xml</title>
<main>
<doc id=002>
<title>doc2</title>
<delt id=0003>
<title>delt1</title>
<text>num1</text>
<text>num1</text>
</delt>
</doc>
</main>
</service>
</xml>

split no 4 delt_0004.xml
<xml>
<service>
<title>split xml</title>
<main>
<doc id=002>
<title>doc2</title>    
<delt id=0004>
<title>delt1</title>
<text>num1</text>
<text>num1</text>
<delt>
</doc>
</main>
</service>
</xml>

Thanks in advance