Australia and the United States launched their biggest joint war games Monday, involving 27,500 troops backed by a US aircraft carrier and scores of ships and planes. The biennial Talisman Sabre exercise pits 20,000 US troops and 7,500 Australian forces against two fictional enemies - the Kamarians and Musorians - in a variety of land and sea-based scenarios designed to test their skills in combat, peacekeeping and humanitarian relief efforts. The exercise, which runs until July 2, will also include 10 US ships, 20 Australian ships and 125 aircraft operating off the coast of Rockhampton in northeastern Queensland state. "The United States and Australia have a long-standing relationship ... we share the same values and interests. Foremost among those interests is the stability and security of the Asia-Pacific region," US Vice Admiral Doug Crowder told reporters on board the USS Blue Ridge in Sydney.