The Qatar Armed Forces are the military forces of Qatar. The country maintains a modest military force of approximately 11,800 men, including an army (8,500), navy (1,800) and air force (1,500). Qatar's defense expenditures accounted for approximately 4.2% of gross national product in 1993, and 1.5% of gross domestic product in 2010, the most recent year available in the SIPRI statistical database. Qatar has recently signed defense pacts with the United States and United Kingdom, as well as with France earlier in 1994. Qatar plays an active role in the collective defense efforts of the Gulf Cooperation Council; the other five members are Saudi Arabia, Kuwait, Bahrain, the UAE, and Oman. The presence of the large Al Udeid Air Base, operated by the United States and several other UN nations, provides a guaranteed source of defense and national security. In 2008 Qatar spent US$2.3 billion on military expenditures, 2.3% of the gross domestic product. Qatari special forces have been trained by France and other Western countries, and are believed to possess considerable skill. They also helped the Libyan rebels during the 2011 Battle of Tripoli.