LONDON, 5 June 2025 — UK100, the cross-party local climate network, has written to the Chief Secretary to the Treasury ahead of the upcoming Spending Review (11 June) urging the Treasury to maintain the £13.2 billion commitment to energy efficiency measures — arguing that the Warm Homes Plan is a critical pillar of Britain's national security strategy.

The letter was sent to Darren Jones MP earlier this week (2 June) before sources leaked to The Guardian that  the Warm Homes plan could be safe from swingeing cuts. It has been signed by UK100 Chief Executive Christopher Hammond and the organisation's four Co-presidents representing cross-party councils across England.

The Warm Homes Plan has been critical to the discussions between the Department of Energy Security and Net Zero and the Treasury, as the Chancellor has looked to find savings in a tight fiscal environment. The letter landed in the Treasury inbox as the government set out its national security priorities. 

With Russia weaponising energy supplies across Europe and the government setting out its ambition to increase defence spending to 3% of GDP, UK100 argues that national security begins at home — and that means ensuring British homes are no longer dependent on volatile fossil fuel markets often manipulated by hostile nations.

Christopher Hammond, Chief Executive of UK100, says:

“National security begins at home. Every poorly insulated house is a vulnerability in our energy defences. Let's not forget about the £44bn that was required to subsidise everyone's bills for one year after the invasion of Ukraine and the energy price spike. This money is gone, we’ll be paying it back for decades, but it had no lasting impact. The Warm Homes plan in comparison, can build a lasting legacy by helping families reduce their bills and improve their quality of life. The programme scales up to enhance our energy independence, that underpins our national resilience."

The letter highlights how Labour's manifesto commitment of £13.2 billion for household energy efficiency upgrades over this parliament delivers far reaching benefits beyond those captured in the Treasury’s Green Book.

Research shows that improving energy efficiency is the fastest way to reduce demand for imported fossil fuels, with every properly insulated home reducing Britain's exposure to global energy price shocks controlled by authoritarian regimes.

Going beyond national security, the letter outlines four critical reasons why the investment in Warm Homes must be protected:

Tackling the cost of living crisis: With energy efficiency being the only guaranteed way to permanently reduce energy bills, local leaders emphasise that "the cheapest energy is the energy we don't use."

Creating local jobs: Research by PwC shows each job in the sector creates more than five extra jobs in the wider supply chain, with the Construction Industry Training Board estimating the sector could support 40,000 jobs annually by 2028.

Improving public health: Cold, damp homes cost the NHS an estimated £1.4 billion annually, with research indicating that getting homes to EPC 'C' standard could prevent 650,000 cases of childhood asthma by 2030.

Delivering for climate: UK100's most recent report found that 70% of local leaders across all political parties identified household energy efficiency as the top priority for meeting local and national climate goals.

Cllr Tracey Dixon, Leader of South Tyneside Council and UK100 Co-president, says:

"Every home we properly insulate is a small victory in an energy war. But it’s more than that. In South Tyneside, we've seen the transformative impact of this work on our residents' lives. Looking beyond targets and numbers on a spreadsheet, this is about warm, healthy homes for families who desperately need support. We will continue to push for the investment our communities need, and we’ll keep making the case for climate action that delivers real benefits for local people."

Research by E3G shows that nearly half a million pensioners could remain vulnerable to high energy bills if the manifesto promise is broken.

Cllr Andy Mellen, Leader of Mid Suffolk Council and UK100 Co-president, adds:

"Rural communities like ours in Mid Suffolk face particular challenges with older housing stock and higher heating costs. We understand more than most that energy independence starts with efficient homes that need less energy in the first place. The Warm Homes Plan pays for itself through lower bills and stronger communities."

Cllr Lucy Nethsingha, Leader of Cambridgeshire County Council and UK100 Co-president, continues:

"Our national security is built on resilient communities that aren't vulnerable to energy price shocks from authoritarian regimes. When families are choosing between heating and eating because of Putin's energy games, that's a national security issue. Energy efficiency is the permanent solution that no dictator can switch off."

Household energy efficiency and the future of the British home will be explored at UK100’s '5 & 25 Local Climate Conference: Beyond Targets' in Birmingham on 13 June, where the organisation will launch a new flagship report examining the wider benefits of local climate action. 

The report includes detailed case studies from local authorities across the UK, including Cambridge and Leeds, demonstrating how energy efficiency programmes deliver enhanced economic resilience and improved public health.

Cllr Richard Clewer, Leader of Wiltshire Council 2021-2025 and UK100 Co-president, concludes:

"The cross-party support for energy efficiency at local level shows this isn't about party politics — it's about protecting our communities and our country. Local leaders understand that every pound spent on insulation is a pound that stays in local pockets rather than flowing to Putin's war chest. That's the kind of strategic thinking our national security demands."

The letter in full:

The Rt Hon Darren Jones MP
Chief Secretary to the Treasury
HM Treasury
1 Horse Guards Road
London, SW1A 2HQ

Monday, June 2, 2025

Re: Commitment to Warm Homes in the Spending Review

Dear Chief Secretary to the Treasury,

As local leaders representing communities across the UK, we are writing to express our serious concern regarding reports that the government may be scaling back its energy efficiency plans in the upcoming spending review.

Labour's manifesto committed £13.2 billion for home retrofit over this parliament. While we welcomed the £3.4 billion announced in the Autumn Budget for 2025-2028, this represents a significant reduction in annual allocations compared to previous spending.

We believe that delivering on the Government's Warm Homes commitment is essential for four key reasons:

1. Tackling the cost of living crisis: The cheapest energy is the energy we don't use. Retrofit is the only guaranteed way to permanently reduce energy bills. In our communities, families are still choosing between heating and eating.

2. Delivering for climate: The cross-party consensus at the local level is clear — in UK100's Local Net Zero 2.0 report, 70% of local leaders across all political parties identified retrofit as the top priority for meeting local and national climate goals.

3. Creating local jobs: PwC research shows each retrofit job creates 5.3 additional jobs in the supply chain. The Construction Industry Training Board estimates retrofit could support 40,000 jobs annually by 2028.

4. Improving public health: Cold, damp homes cost the NHS an estimated £1.4 billion annually. Research indicates getting homes to EPC 'C' could prevent 650,000 cases of childhood asthma by 2030.

The energy efficiency of the UK's housing stock is crucial for meeting our climate targets, reducing fuel poverty, and creating green jobs across our communities. As local leaders, we see firsthand how investment in retrofit delivers multiple benefits for our residents.

We respectfully request a meeting to give you the opportunity to:
• Hear from our members on the transformative economic, climate and social impact of their retrofit schemes
• How local authorities can best partner with national government to deliver effective retrofit programmes

We look forward to your response and to working collaboratively to ensure this vital investment is protected.

Yours sincerely,

Christopher Hammond, Chief Executive, UK100
Cllr Tracey Dixon, Leader of South Tyneside Council, UK100 Co-President
Cllr Andy Mellen, Leader of Mid Suffolk Council, UK100 Co-President
Cllr Lucy Nethsingha, Leader of Cambridgeshire County Council, UK100 Co-President
Cllr Richard Clewer, Leader of Wiltshire Council 2021-2025, UK100 Co-President