Army chief lays out plan for autonomy in future warfare with ambitions to ‘strike deep, defend forward and build stronger’

Planning to speak at a conference hosted by the Royal United Services Institute, General Walker will argue it is armies that “decide outcomes” in war and will continue to do so.

He will say: “Only armies seize and hold ground, and only armies remain when wars end. The army ‘buys’ the nation not just battlefield success in isolation but decisive weight at the point it matters.

“The army that adapts fastest – wins. And the deeper change is cultural, not just technological.”

The UK army is at its smallest size since the Napoleonic era.

Historical records show that at the start of the Napoleonic Wars in 1792, the UK Army Regular Forces numbered around 17,000, rising sharply to 237,000 by 1814 as the conflict escalated.

The fully trained UK Army Regular Forces as of October 2025 stood at just 66,250, a figure last seen in 1799, before the wars against Napoleon reached their height.

General Walker will also reflect on a year of reforms to the army before outlining the military’s ambitions to “strike deep, defend forward and build stronger”.

He will continue: “I have been clear to industry: in the future, no crewed platform should ever deploy in future without uncrewed ground vehicles – the utility vehicle of the 21st century.”

The army is moving towards a 20-40-40 fighting system, which consists of one fifth of force delivered via heavy equipment such as tanks, 40 per cent through “attritable” (uncrewed) autonomous machinery such as drones and the rest through high-capacity firepower.

General Walker described this combination as “the three rings of modern lethality”.

He will say: “We must pivot everyone hard to the ‘20-40-40’ fighting system – the three rings of modern lethality.”

His speech will be followed by an address by the new Defence Secretary Dan Jarvis, who succeeded John Healey after he resigned on June 11 over disagreements on the Government’s long-awaited Defence Investment Plan (Dip).

Mr Healey said in his resignation letter to the now-outgoing Sir Keir Starmer the Dip’s current proposed funding was falling short, with only £13.5billion extra allotted to defence, leaving a £14.5billion shortfall of what is needed.

He wrote in his letter to Sir Keir: “This new era for defence required further investment through the Defence Investment Plan.

“The excellent and extensive cross-government work that completed in January – overseen by you, me and the Chancellor – confirmed the scale of the challenge and the rising demands on defence.

“Since then, you have been unable, and the Treasury has been unwilling, to commit the resources that the nation needs to defend the country at this time of rising threats.”

Deputy Prime Minister David Lammy said on Monday the Government is planning to publish the Dip before July 7.

However, it is understood the overall sum of money allocated will not change.

Al Carns, former armed forces minister who also resigned from his frontbench position, has raised the alarm over the current proposed Dip.

He said last week the unpublished proposal is “inadequate to deal with the threat we face”.

The former colonel pointed the finger at Rachel Reeves’ department for the plan’s lack of funding, accusing the Treasury of treating “defence as a cost to be contained”.

He said: “The Defence Investment Plan is inadequate to deal with the threat we face. That figure was not set by the threat, but by the Treasury, which treats defence as a cost to be contained.”