British Armed Forces,[b] also known as Her Majesty's Armed Forces

Expeditionary forces[edit]
The British Armed Forces place significant importance in the ability to conduct expeditionary warfare.^[67] While the armed forces are expeditionary in nature, it maintains a core of "high readiness" forces trained and equipped to deploy at very short notice, these include; the Joint Expeditionary Force (Maritime) (Royal Navy), 3 Commando Brigade (Royal Marines), and 16 Air Assault Brigade (British Army). Frequently, these forces will act as part of a larger tri-service effort, under the direction of Permanent Joint Headquarters, or along with like-minded allies under the UK Joint Expeditionary Force. Similarly, under the auspices of NATO, such expeditionary forces are designed to meet Britain's obligations to the Allied Rapid Reaction Corps and other NATO operations.
In 2010, the governments of the United Kingdom and France signed the Lancaster House Treaties which committed both governments to the creation of a Franco-British Combined Joint Expeditionary Force.^[101] It is envisaged as a deployable joint force, for use in a wide range of crisis scenarios, up to and including high intensity combat operations. As a joint force it involves all three armed Services: a land component composed of formations at national brigade level, maritime and air components with their associated Headquarters, together with logistics and support functions.^[102]
The Armed Forces[edit]
Royal Navy[edit]
HMS Queen Elizabeth, a Queen Elizabeth-class supercarrier on sea trials in June 2017
Main article: Royal Navy
The Royal Navy is a technologically sophisticated naval force,^[103] and as of April 2022 consists of 72 commissioned ships with an additional 11 support vessels of various types operated by the Royal Fleet Auxiliary. Command of deployable assets is exercised by the Fleet Commander of the Naval Service.^[104] Personnel matters are the responsibility of the Second Sea Lord/Commander-in-Chief Naval Home Command, an appointment usually held by a vice-admiral.^[105]
The Surface Fleet consists of aircraft carriers, amphibious warfare ships, destroyers, frigates, patrol vessels, mine-countermeasure vessels, and other miscellaneous vessels. The Surface Fleet has been structured around a single fleet since the abolition of the Eastern and Western fleets in 1971.^[106] The recently built Type 45 destroyers are technologically advanced air-defence destroyers. The Royal Navy has commissioned two Queen Elizabeth-class aircraft carriers, embarking an air-group including the advanced fifth-generation multi-role fighter, the F-35B.^[107]
A submarine service has existed within the Royal Navy for more than 100 years. The Submarine Service's four Vanguard-class nuclear-powered submarines carry Lockheed Martin's Trident II ballistic missiles, forming the United Kingdom's nuclear deterrent. Seven Astute-class nuclear-powered attack submarines have been ordered, with four completed and three under construction. The Astute class are the most advanced and largest fleet submarines ever built for the Royal Navy, and will maintain Britain's nuclear-powered submarine fleet capabilities for decades to come.