Retrieving XML search results

I have signed up for a Google Site Search custom search engine. This has given me the following code to embed in the page where I want the search box:
<div id="cse" style="width: 100%;">Loading</div>
<script src="http://www.google.com/jsapi" type="text/javascript"></script>
<script type="text/javascript">
  google.load('search', '1', {language : 'en'});
  google.setOnLoadCallback(function(){
    var customSearchControl = new google.search.CustomSearchControl('unique_cse_code');
    customSearchControl.setResultSetSize(google.search.Search.FILTERED_CSE_RESULTSET);
    customSearchControl.draw('cse');
  }, true);
</script>
I've inserted it into a new page on my site and it works.
However, I want to be able to access the XML feed of resu ...