Rearm now or risk ruin: Britain faces a shrinking three-year window to prepare for war as Russia rearms at speed, experts warn

The UK cannot afford to delay its long-awaited Defence Investment Plan any longer, according to Andriy Dovbenko, Founder of UK-Ukraine TechExchange, writing exclusively for LBC Opinion.

In a stark warning, Mr Dovbenko argues that Britain is moving too slowly to bolster its own defence and security, despite being one of Ukraine’s closest allies and increasingly framed by the Kremlin as a principal adversary.

“The war in Ukraine has now lasted almost as long as the First World War,” he writes, pointing to the profound global consequences of the conflict, from disrupted supply chains to renewed geopolitical tensions over critical minerals.

Yet while Ukraine has compressed decades of defence innovation into months, Britain remains constrained by lengthy procurement cycles and uncertainty over future spending, he argues.

Mr Dovbenko warns that without a clear, accelerated investment plan, the UK risks undermining its standing within NATO at a time of growing threats from Russia. He highlights the rapid evolution of drone warfare, electronic warfare and autonomous systems on the Ukrainian battlefield, capabilities he says Western forces are not yet fully prepared to counter.

“If Western forces were to face a battle-hardened Russian drone unit today, they risk suffering the exact same fate seen in recent exercises,” he writes, referring to NATO drills in which mechanised units were reportedly tracked and eliminated with alarming ease.

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His intervention comes as ministers signal that decisions on defence spending could be imminent.

In an exclusive interview with my LBC colleague, Joseph Draper, Armed Forces Minister Al Carns suggested the Government could announce new funding for defence “in the next couple of weeks” to ensure the armed forces have “the right capabilities”.

Speaking at the Chatham House Security and Defence Conference in London, Mr Carns acknowledged that the Cabinet faced “difficult choices” but hinted that movement was coming soon.

“In the next couple of weeks we’ve got decisions coming, so I would keep posted, and you will see us moving at the right speed to deliver the right capabilities for our armed forces,” he told LBC.

A Ministry of Defence source later clarified that the Minister was referring to “general defence investment” rather than the formal Defence Investment Plan, a much-anticipated document expected in the coming months.

The signals come amid mounting concern within government and the military. As reported by LBC in November, senior figures warned that the MoD faces a funding “crisis” and could be forced to cut key capabilities within two years.

NATO assessments have also warned that Russia could be in a position to attack a NATO country within three to five years, raising fears that the UK risks falling behind some European allies in rearmament.

The Government has committed to spending 2.6 per cent of GDP on defence by 2027, rising to 3 per cent in the next Parliament.

However, there are reports that the Prime Minister is considering accelerating the timetable, potentially meeting the 3 per cent target by 2029, which could amount to an additional £17 billion a year.

The Chancellor, Rachel Reeves, is said to have pushed back against calls from the Ministry of Defence for billions more in immediate funding.

For Mr Dovbenko, the issue is not simply the size of the budget, but how quickly and intelligently it is deployed. He argues that decade-long procurement cycles are no longer fit for purpose and calls for rapid acquisition pathways, shortened to 12 to 24 months, alongside expanded munitions production and more resilient supply chains.

Crucially, he says Britain must deepen structural partnerships with Ukrainian manufacturers, absorbing the “battlefield DNA” forged through four years of high-intensity conflict.

“The UK has a huge opportunity to lead,” he writes. “Now is the time to back up the promises to learn from Ukraine with concrete plans.”

With ministers hinting at imminent spending decisions and military leaders warning of shrinking margins for error, the question is no longer whether Britain needs to rearm, but how fast it is willing to move.