As many as 3,000 military personnel will be involved in supporting a pilot of mass coronavirus testing in Liverpool.
Tests will be offered to everyone across the city with all residents and workers able to be tested regularly from Friday, regardless of whether they have symptoms.
Prime Minister Boris Johnson said the approach "has the potential to be a powerful new weapon in our fight against COVID-19".
It follows the announcement that the British Army will be used in the rollout of "rapid turnaround tests" for coronavirus, which will form part of the initiative in Liverpool.
The Defence Secretary said around 47 testing stations will be set up in the city, with the military helping deliver "at pace and at scale".
Ben Wallace stated that personnel will not be involved in isolation enforcement, saying the military would be focusing on supporting the NHS and COVID-19 testing.
He also added that the 7,500 servicemen and women making up the Winter Support Force could be increased.
The city's mayor, Joe Anderson, told Forces News: "We value and welcome their [the military's] expertise and their logistic expertise as well, so it's important for us to have that alongside us as we try to tackle this virus."
He said the Armed Forces will be "manning the mobile units that we have, where they will go to target specific areas within the city", adding: "They will be working alongside ourselves as the council, but also our public health officials as well, so it’s a partnership approach.
"We’re very much, in a way, reliant on them and their expertise in certain areas and they’ll be relying on us to take them to the areas where we know this will work."
Watch: Liverpool's mayor spoke to Forces News ahead of the military's support in the city.
Retired Lieutenant General James Bashall told Forces News it is "not a huge challenge" for the military to deploy personnel in this way.
"It is something the military are used to," he said.
"They're used to moving people, they're used to planning and they're used to sustaining and looking after large groups of people."
The former Commander, Home Command, also explained that the military is offering an "immediate provision of manpower".
"The Army, particularly, offers the nation a guaranteed reserve that can quickly go and do this job," he added.
The provision of around half a million new, rapid turnaround tests is happening at the request of and in close collaboration with local leaders, the Department of Health and Social Care (DHSC) said.
Armed Forces personnel, who have been involved in testing since the coronavirus pandemic started earlier this year, will be on hand to help with planning logistics locally and delivering the extra capacity.
The plan is to use new rapid turnaround tests – alongside existing swab tests – to find asymptomatic cases in the city in order to help prevent and reduce transmission in the community.
There will also be Lamp (loop-mediated isothermal amplification) technology deployed in Liverpool University Hospitals NHS Foundation Trust for NHS staff, promising to deliver significant volumes of tests.
Liverpool recorded 366.4 coronavirus cases per 100,000 people in the seven days to 29 October.
The DHSC added that the pilot will help "inform a blueprint for how mass testing can be achieved and how fast and reliable COVID-19 testing can be delivered at scale".
Testing will be carried out in new and existing sites across the city, including in hospitals, care home settings, schools, universities, workplaces and using at-home kits.
People can book a test online, by walk-up, or by invitation from the local authority, and Health Secretary Matt Hancock urged people to "play their part" by getting a test.
Prime Minister Boris Johnson said: "These tests will help identify the many thousands of people in the city who don't have symptoms but can still infect others without knowing.
"Dependent on their success in Liverpool, we will aim to distribute millions of these new rapid tests between now and Christmas and empower local communities to use them to drive down transmission in their areas.
"It is early days, but this kind of mass testing has the potential to be a powerful new weapon in our fight against COVID-19," he added.
Recently, members of the Royal Air Force were sent to Birmingham to distribute test kits to homes in the city as part of a Drop and Collect initiative.
Meanwhile, the "Winter Support Force" made up of 7,500 Armed Forces personnel has been formed to help authorities deal with COVID-19 in the coming months.
Defence Secretary Ben Wallace said on Monday the Ministry of Defence is "examining some significant asks from a number of local authorities".
It comes after the announcement of second nationwide lockdown in England, set to come into force on Thursday.