Peer-to-Peer (P2P) data integration combines the P2P infrastructure with traditional scheme-based data integration techniques. Some of the primary problems in this research area are the techniques to be used for querying, indexing and distributing documents among peers in a network especially when document files are in XML format. In order to handle this problem we describe an XML P2P system that efficiently distributes a set of clustered XML documents in a P2P network in order to speed-up user queries. The novelty of the proposed system lies in the efficient distribution of the XML documents and the construction of an appropriate virtual index on top of the network peers.