Keir Starmer is facing a mounting Labour backlash over his decision to slash foreign aid to boost defence spending.

The prime minister announced last week that the amount of money the government spends on the military will increase from 2.3% of Gross National Income to 2.5% from 2027, with the aim of hitting 3% in the next parliament.

International development minister Anneliese Dodds – once Starmer’s shadow chancellor – dramatically quit 48 hours later.

The PM is now expected come face-to-face with the fury from some Labour MPs in the Commons today.

As first reported by The Sun, Starmer is expected to be hit with a letter from disgruntled backbenchers unhappy at the move just before PMQs.

The note, seen by HuffPost UK, warns that cutting UK aid will have a “devastating impact on communities which are facing humanitarian crises, the climate crisis and economic insecurity”.

The letter claims cutting development funds to boost defence is “illogical” because foreign aid spending “reduces the causes of instability” and reduces global health security.

It’s not clear how many MPs have signed the letter, but there are murmurings of a wider fightback against the plan.

One Labour source told HuffPost UK that there is frustration across all wings of the party over the aid cuts.

David Taylor, a former adviser to Gordon Brown who was elected last year, welcomed the boost to defence but said he was “pained” by the cut to foreign aid, and wanted to get back on track to 0.7%.

He called for the government to agree to more innovative ways to support development across the world.

The Labour Campaign for International Development – which was founded by Taylor – also released their own statement at the time of Starmer’s announcement, calling for the government to “think again”.

It said that the cut would take aid spending levels to their lowest since 1990s and “see the world’s most vulnerable pay the price”.

“Such a severe cut will see fragile states made more fragile, poor people made poorer, and the impacts of climate change made harsher,” LCID added.

Another MP from the new cohort, Alice Macdonald, wrote on X last week: “I welcome the uplift in the defence budget, but, as the prime minister himself recognised, cutting the aid budget is a very difficult decision.

“Aid matters – not only to tackle poverty but importantly for our own security as I underlined in the House today. I want to see us get back to 0.7% as soon as economic circumstances allow.”

Labour veterans have also condemned the move.

Writing in the Independent, veteran left-winger Diane Abbott said: “Cutting the aid budget to pay for a rearmament drive is the clearest expression of the completely wrong priorities of this Labour government. The distance between this policy and what might be called Labour values is a chasm. It will not add to our security and is morally indefensible.”

Emily Thornberry, who was in Starmer’s shadow cabinet but not invited to take on a government role once Labour were elected, welcomed the defence spending boost – but also noted British security relies on a combination of soft and hard power.

“Keir has himself said that he wants to prioritise Ukraine and Gaza and Sudan,” she told Channel 4 News.

Thornberry, who is now the chair of the foreign affairs committee, said: “And my concern is, is that the the cuts to the overseas development aid is so much that given that a third of it has to be spent on people claiming asylum and going into asylum hotels, that there’s so little left that by the time we pay our dues to the various international organisations, there’s very little left and there may not even be enough to do those three priorities and we may find ourselves.”