London, UK – The United Kingdom will build 12 new attack submarines as part of a sweeping plan to modernise its military capabilities, Prime Minister Keir Starmer announced Monday, as his government launched a comprehensive Strategic Defence Review aimed at addressing the nation’s evolving security challenges.

Unveiled amid rising geopolitical instability, the review marks a bold shift in Britain’s defence posture, highlighting the threat from Russia, the rapid transformation of warfare through artificial intelligence and drones, and the uncertainties surrounding U.S. commitment to European security.

“There is greater instability on defence and security than there has been for many, many years, and greater threats,” Starmer said in a BBC interview. He described the review as “a blueprint for strength and security for decades to come.”

The document, led by former NATO Secretary General George Robertson, warns that Britain is entering “a new era of threat,” and outlines measures to enhance military readiness, prioritise NATO coordination, and increase domestic defence production.

Key Defence Commitments

• 12 New Attack Submarines: The UK will construct up to a dozen new submarines under the AUKUS security alliance with the U.S. and Australia.
• £15 Billion for Nuclear Warheads: Significant investment will be directed at the UK’s nuclear deterrent capabilities.
• Cyber Command: A £1 billion initiative to establish a dedicated cyber warfare unit.
• Expanded Munitions Production: £1.5 billion will fund at least six new factories and ramp up long-range weapons production.
• 7,000 Domestically Built Long-Range Weapons: The UK aims to boost its stockpiles with British-made munitions.
• Increased Defence Spending: Defence spending will rise to 2.5% of GDP by 2027, with a long-term goal of reaching 3% in the next parliamentary term.

Strategic Focus

Defence Secretary John Healey stressed the urgency behind the new strategy: “It’s growing Russian aggression. It’s daily cyberattacks, new nuclear risks, and increasing tension in other parts of the world.”

The review singles out Russia as an “immediate and pressing” threat, while labelling China a “sophisticated and persistent challenge.” Starmer, in an op-ed for The Sun, notably omitted any direct criticism of China, in a shift toward restoring diplomatic ties damaged under the previous Conservative government.

The so-called “deadly quartet” of Russia, China, Iran, and North Korea was cited by Robertson as a central concern for UK national security.

Amid fears of declining U.S. support under a potential second Trump presidency, the UK is also reportedly considering acquiring nuclear-capable aircraft from the U.S. to strengthen its deterrence capabilities. While Healey declined to confirm the report, he underscored the importance of deterrence in safeguarding Britain’s interests.

Funding and Trade-Offs

To fund this historic military build-up, the Labour government has pledged to cut overseas aid. This controversial move underlines the scale of the investment: the largest sustained defence spending increase since the Cold War.

The last Strategic Defence Review was published in 2021 and updated in 2023 in response to Russia’s invasion of Ukraine. The 2025 iteration is more expansive, addressing hybrid threats and emerging technologies with a long-term defence strategy anchored in NATO collaboration and domestic resilience.

As global tensions rise, Britain’s recalibrated defence posture signals a clear message: the country is preparing for a new age of complex and unpredictable warfare.