Middle East crisis: The military firepower the UK and US have at their disposal in the Gulf
British forces have joined the US in targeting more sites used by the Iranian-backed Houthi fighters in Yemen.
The airstrikes were in retaliation for Houthi drone and missile attacks on commercial shipping which began after the start of the Israel-Hamas war.
The Yemeni rebel group has declared its support for Hamas in Gaza and said it would target vessels heading for Israel.
In the wake of the latest strikes, Sky News profiles the military hardware and weapons the UK and America have at their disposal in the region.
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Britain
HMS Diamond
The Type 45 destroyer has already been engaged in downing drones and missiles fired by Houthis against civilian ships in the Red Sea.
Diamond's sleek lines are designed for stealth at sea, appearing virtually invisible on enemy radar.
HMS Diamond, which has cutting-edge military sensors to detect and track multiple targets, is equipped with 48 Sea Viper missiles - long-range, precision weapons capable of reaching supersonic speeds of Mach 4.5 and each costing more than £1m.
The weapon system can launch eight missiles in under 10 seconds and guide up to 16 missiles simultaneously.
Other armaments include a 4.5in main gun, 30mm cannon, 20mm rapid-fire Gatling guns, anti-ship Harpoon missiles and an anti-torpedo defence system.
The destroyer, which can reach 30 knots and has a range of 7,000 nautical miles, is equipped with a distinctive SAMPSON radar system - a large, spherical surveillance device that can detect and track threats from over 250 miles away, as well as guide friendly missiles.
Unlike conventional radars, it can perform several functions at once, has immense range and accuracy and is immune to enemy jamming.
It also has a flight deck for a single helicopter.
HMS Lancaster
The Type 23 frigate, which has a top speed of 28 knots and a range of 7,800 nautical miles, is the core of the Royal Navy's frontline fleet because of its all-round operational effectiveness.
Originally designed for anti-submarine warfare during the Cold War, its technology and weaponry has since been updated to handle virtually any threat.
More on Yemen strikes:
Analysis: A busy shipping lane can't become Wild West
Analysis: Strikes on Yemen could trigger regional war
Who are the Houthis?
The warship's 4.5-inch gun can provide artillery bombardment of shore targets, firing up to 24 high explosive shells per minute (each weighing 40kg) up to 18 miles away.
It is also equipped with Harpoon long-range anti-ship missiles and the cutting-edge Sea Ceptor air defence system, which can guard an area of 500 square miles and engage multiple targets at the same time.
HMS Richmond, another Type 23 frigate, is also on its way to the region.
RAF Typhoons
Although not based in the Gulf, four of the multi-role combat aircraft, flying from Cyprus, were used to carry out strikes against Houthi military targets in Yemen.
The long-range mission was made possible by a Voyager air refuelling tanker.
Capable of reaching a top speed of Mach 1.8, the FGR4 Typhoon has a maximum altitude of 55,000ft.
From brakes off it can reach Mach 1.5 at 35,000ft in less than two minutes 30 seconds.
Armed with a 27mm Mauser cannon it is capable of range of missiles and precision-guided bombs.
Paveway IV guided bombs
The highly accurate precision weapons used by the Typhoons in the attacks on Houthi facilities are capable of destroying the majority of targets while minimising collateral damage.
The RAF's go-to weapon has been in operational use since 2008.
Costing about £30,000 each and weighing 226kg, the Paveway has four main parts - the guidance system in the front, a 500lb warhead in the middle (which can penetrate concrete) and, at the back, the tail section guides the bomb, with a smart fuse to control how it detonates.
GPS is one way the bomb can be guided to its target, but as a dual-mode weapon it can also be directed using a laser.
United States
USS Dwight D Eisenhower
The nuclear-powered Nimitz-class aircraft carrier was sent to the region to "deter hostile actions against Israel or any efforts toward widening this war following Hamas's attack on Israel", according to US Defence Secretary Lloyd Austin.
Described by the US Navy as its "finest five-star aircraft carrier", the 1,092ft-long vessel has a top speed of more than 30 knots.
With a personnel of around 5,000 it can carry in the region of 60 aircraft.
It is accompanied by a Carrier Strike Group, which includes USS Philippine Sea, a guided-missile cruiser, and USS Gravely and USS Mason.
USS Laboon, a destroyer, is also operating in the Red Sea.
The warships have a range of armaments including surface-to-air missiles, guns and and close-in weapons systems.
They also have electronic warfare capabilities that could cut the links between drones and their on-shore controllers.
F/A-18 Super Hornet
The advanced warplane is the US Navy's main strike aircraft.
It has been likened to a power tool with various attachments in that it can be configured for different types of missions.
Equipped with a 20mm rotary cannon it can also carry air-to-air and air-to-surface missiles and a variety of other weapons.
The jet can reach a speed of Mach 1.8 and climb to 50,000ft, with a range of 1,275 nautical miles.
The advanced cockpit system includes a touchscreen display providing the pilot with the capability to see, track and target multiple long-range targets.
Tomahawk missiles
The US Navy's low-flying Tomahawk cruise missiles can deliver a 1,000lb conventional warhead hundreds of miles inland.
Launched from either ships or submarines, Tomahawks fly at subsonic speeds on "evasive" or indirect routes which can beat air defence systems.
The missiles are GPS-guided so can change targets or courses after launch.
