<?php
 
$xml = <<<'XML'
<?xml version="1.0"?>
    <user>
 
        <urls>
          <link>www.weblink-1.com</link>
          <link> www.weblink-2.com</link>
          <link> www.weblink-3.com</link>
          <link> www.weblink-4.com</link>
          <link> www.weblink-5.com</link>
        </urls>
 
    </user>
XML;
 
$dom = new DOMDocument();
$dom->loadXML($xml);
 
$xpath = new DOMXPath($dom);
 
foreach($xpath->query('//link[contains(., "www.weblink-4.com")]') as $node) {
	$node->parentNode->removeChild($node);
}
 
echo $dom->saveXML();
 

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