Allied warplanes in a coalition led by France and backed by Arab nations have gone into action to stop Libyan leader Muammar Gaddafi's forces attacking the rebel-held city of Benghazi .
U.S. and British ships and submarines fired more than 110 Tomahawk cruise missiles at Libyan targets to take out their air defences, although no U.S. aircraft were flying over Libya.
Following are assets that are being used, or could be used, in action against Muammar Gaddafi's troops and those belonging to his military:
France has some 20 fighter jets deployed in an initial operation in Libya, including Rafale multirole war planes, Mirage fighter jets and at least one AWACS surveillance aircraft. The target area involved is a area 62 by 93 miles (100 km by 150 km) around the rebel-controlled city of Benghazi.
The French operation is being run out of the Solenzara air base in the Mediterranean island of Corsica, around an hour's flight from Libya in a fighter jet.
France's Charles de Gaulle aircraft carrier is on the French Mediterranean coast and will head to Libya around midday on Sunday. It could reach the Libyan coast by late Monday carrying 15 fighter jets. Its battle group includes three frigates, a fuel-supply ship and an attack submarine.
France also has air forces bases near the Mediterranean towns of Marseille and Istres, about an hour and a half from Libya. Airborne refuelling tanker aircraft were ready on Friday to deploy from Istres.
France rejoined NATO's military command in 2009, reversing four decades of self-imposed exile
Britain deployed its air forces later on Saturday, likely to be Typhoon patrol jets and all-weather Tornado attack aircraft normally based at Royal Air Force bases in Scotland and the eastern county of Norfolk, as well as air-to-air refuelling and surveillance aircraft.
Britain has two frigates off the Libyan coast: HMS Cumberland and HMS Westminster. The Ministry of Defence said it was not clear if they would be used in any operation and added that destroyers could also be deployed.
The United States started a "limited military action" in Libya several hours after France that included launching strikes along the Libyan coast that would target Libyan air defences.
The U.S. military deployed planes, cruise missiles and electronic attacks, the Pentagon said.
A defence official said the U.S. Navy has three submarines outfitted with Tomahawk missiles in the Mediterranean ready to participate, including attack submarines Newport News and the Providence. They were were joined by two Navy ships.
Tomahawk missiles can cripple aircraft of anti-aircraft defences in a no-fly operation.
In all, the U.S. Navy has five combat ships in the Mediterranean, including at least one guided missile destroyer, but there are no U.S. aircraft carriers close to Libya.
The USS Enterprise, which was recently stationed in the Red Sea, has been moved eastwards, away from Libya, to join the USS Carl Vinson,in the Arabian Sea to support Afghanistan operations.
Aviano, south of the Alps in Italy, is the region's only U.S. air base with aircraft assigned to it -- 42 F-16s. The Pentagon has not discussed the positioning of other planes in the region. The United States has a range of Mediterranean military bases and installations in Italy, Greece, Spain and Turkey.
Canada's HMCS Charlottetown warship has joined naval actions, including a naval blockade, taking place off Libya, Prime Minister Stephen Harper told reporters.
Canadian fighter jets have reached the region but need another day or two of preparation before they can join the mission, a Canadian government spokesman said.
Italy has deployed dozens of combat aircraft at its base at Trapani, in western Sicily in readiness for possible involvement in airstrikes on Libya.
Tornado fighters that can be used to destroying enemy air defences and radar as well as F-16s and Eurofighters used for air-to-air defence have been moved to Trapani from bases in Piacenza in northern Italy, Gioia del Colle in Apulia.
Italy has also offered the use of a NATO base near the city of Naples for joint command centre for the joint operation, and could participate later on in military activities, Prime Minister Silvio Berlusconi said.
Defence Minister Ignazio La Russa said in all seven bases in Italy -- at Amendola, Gioia del Colle, Sigonella, Aviano, Trapani, Decimomannu and Pantelleria -- were available and some allies had already asked to use them.
Five of them are on the southern mainland or Sicily, making them some of the closest available bases to Libya.