The UK Ministry of Defence (MoD) announced that the Anglo-French Combined Joint Expeditionary Force (CJEF) has reached full operating capacity.
The joint military force is now able to deploy 10,000 personnel to respond to shared threats.
They can also carry out tasks such as high-intensity operations, peacekeeping, disaster relief or humanitarian assistance.
The CJEF was established as part of the defence and security, and on nuclear cooperation treaties signed at Lancaster House by the UK and France in 2010.
This week, paratroopers from the two forces will take part in Exercise Wessex Storm on Salisbury Plain under the CJEF training.
The French 2e Regiment Etranger de Parachutistes (2e REP) soldiers will be attached to the 2 PARA Battlegroup.
UK Defence Secretary Ben Wallace said: “Today, the UK and France face a range of security threats of increasing scale and complexity.
“Having a highly capable, high readiness force is essential if we are to protect both UK security and the security of our Nato allies.
“It is testament to our close defence relationship that we have achieved all the milestones set out in the Lancaster House treaties ten years ago, working together to protect our mutual interests.”
The two nations also set other goals which included the establishment of joint nuclear facility and the development of UK and French complex weapons sectors.
The UK MoD noted that the goals were established within the set time frame of ten years.