Sign up to the Inside Politics email for your free daily briefing on the biggest stories in UK politics Get our free Inside Politics email Liz Truss told parliament today that she would "absolutely" be sticking to her leadership campaign pledge not to cut spending on public services.
But there's good reason to think her claim is not what it seems.
The promise has raised eyebrows because the prime minister is due to borrow £45 billion to cut taxes, mostly for wealthier households.
And yet her government is expected to announce a debt reduction plan to satisfy financial markets, which went haywire over her unfunded tax cuts.
So how is the prime minister able to make such a promise? Where is the sleight of hand?
One clue came immediately after the Commons session. Questioned after PMQs by reporters in Westminster Ms Truss's spokesperson warned while she would of course stick to the promise, there would be "difficult decisions" on spending.
This raised alarm bells because the tone was rather different from the prime minister's own in the chamber 30 minutes earlier
Pushed further, the spokesperson crucially would not say whether spending pledges made in the government's existing spending plan would be upgraded in line with inflation.
This is crucial, because inflation is currently running at around 10 per cent.
So a 10 per cent increase is needed just to stand still, and not increasing allocations would represent a 10 per cent cut to departments.
So when Truss says she won't cut public spending, she means in what economists call "cash terms", rather than "real terms".
UK news in picturesShow all 50 UK news in pictures 21 October 2022 Sculptor Peter McKenna puts the finishing touches to a pumpkin that will form part of the ‘Planet A’ Hebden Bridge Pumpkin Trail in the West Yorkshire town
PA
UK news in pictures 20 October 2022 Britain’s Prime Minister Liz Truss delivers a speech outside of 10 Downing Street in central London to announce her resignation
AFP/Getty
UK news in pictures 19 October 2022 Salmon leap up Stainforth Force on the River Ribble in the Yorkshire Dales as they swim upriver to their spawning grounds during the annual Salmon migration
PA
UK news in pictures 18 October 2022 Just Stop Oil protesters continue their protest for a second day on the Queen Elizabeth II Bridge, which links Kent and Essex and which remains closed for traffic, after it was scaled by two climbers from the group
PA
UK news in pictures 17 October 2022 Hundreds of students take part in the traditional Raisin Monday foam fight on St Salvator's Lower College Lawn at the University of St Andrews in Fife
PA
UK news in pictures 16 October 2022 A protester holds a placard during a march into central London at a demonstration by the climate change protest group Extinction Rebellion
AFP/Getty
UK news in pictures 15 October 2022 A member of the public drags an activist who is blocking the road during a "Just Stop Oil" protest, in London, Britain
REUTERS
UK news in pictures 14 October 2022 Germany’s Women’s double skulls during day one of the World Rowing Beach Sprint Finals at Saundersfoot beach, Pembrokeshire
PA
UK news in pictures 13 October 2022 Family and mourners arrive at St Michael's Church, in Creeslough, for the funeral mass of 49-year-old mother of four Martina Martin, who died following an explosion at the Applegreen service station in the village of Creeslough in Co Donegal on Friday
PA
UK news in pictures 12 October 2022 Motorists in Coventry pass trees showing autumnal colour
PA
UK news in pictures 11 October 2022 A woman and her dog in the the North Sea at Tynemouth Longsands beach before sunrise
PA
UK news in pictures 10 October 2022 Police officers remove a campaigner from a Just Stop Oil protest on The Mall, near Buckingham Palace, London
PA
UK news in pictures 9 October 2022 A drummer plays during the Diwali on the Square celebration, in Trafalgar Square, London
PA
UK news in pictures 8 October 2022 Timothee Chalamet attending the UK premiere of Bones and All during the BFI London Film Festival 2022 at the Royal Festival Hall, Southbank Centre, London
PA
UK news in pictures 7 October 2022 Two young male fallow deer lock antlers in Dublin’s Phoenix park as rutting season begins
PA
UK news in pictures 6 October 2022 The Princess of Wales during a cocktail making competition during a visit to Trademarket, a new outdoor street-food and retail market situated in Belfast city centre, as part of the royal visit to Northern Ireland
PA
UK news in pictures 5 October 2022 Greenpeace protesters interrupt Prime Minister Liz Truss as she delivers her keynote speech to the Conservative Party annual conference
PA
UK news in pictures 4 October 2022 Prime Minister Liz Truss and Britain’s Chancellor of the Exchequer Kwasi Kwarteng wearing hard hats and hi-vis jackets, visit a construction site for a medical innovation campus in Birmingham
AFP/Getty
UK news in pictures 3 October 2022 British artist Sam Cox, aka Mr Doodle, reveals the Doodle House, a twelve-room mansion at Tenterden, in Kent, which has been covered, inside and out in the artist's trademark monochrome, cartoonish hand-drawn doodles
PA
UK news in pictures 2 October 2022 Erling Haaland celebrates after scoring Manchester City's second goal against Manchester United at Etihad Stadium. Haaland went on to score a hattrick, his third of the season in the Premier League. City beat United 6-3.
Manchester City FC/Getty
UK news in pictures 1 October 2022 Protesters hold up flags and placards at a protest in London. A variety of protest groups including Enough is Enough, Don't Pay and Just Stop Oil all demonstrated on the day
AFP/Getty
UK news in pictures 30 September 2022 British Prime Minister Liz Truss, who has not been seen in days, leaves the back of Downing Street after a meeting with Office For Budget Responsibility following the release of her government’s mini-budget
Getty
UK news in pictures 29 September 2022 The Virginia creeper foliage on the Tu Hwnt i'r Bont (Beyond the Bridge) Llanwrst, Conwy North Wales, has changed colour from green to red in at the start of Autumn. The building was built in 1480 as a residential dwelling but has been a tearoom for over 50 years
PA
UK news in pictures 28 September 2022 Criminal barristers from the Criminal Bar Association (CBA), demonstrates outside the Royal Courts of Justice in London, as part of their ongoing pay row with the Government
PA
UK news in pictures 27 September 2022 David White, Garter King of Arms, poses with an envelope franked with the new cypher of King Charles III 'CIIIR', after it was printed in the Court Post Office at Buckingham Palace in central London
AFP/Getty
UK news in pictures 26 September 2022 A gallery staff member poses next to a painting by Lucian Freud - Self-portrait (Fragment), 1956 - on show at a photocall for the Credit Suisse exhibition - Lucian Freud: New Perspectives at the National Gallery in London
PA
UK news in pictures 25 September 2022 Labour leader, Sir Keir Starmer is interviewed by Laura Kuenssberg in Liverpool before the start of the Labour Party annual Conference which he opened with a tribute to Queen Elizabeth II and sang the national anthem
PA
UK news in pictures 24 September 2022 Handout photo issued by Buckingham Palace of the ledger stone at the King George VI Memorial Chapel, St George's Chapel, Windsor Castle
PA
UK news in pictures 23 September 2022 A climate change activist protests against UK private jets while lighting his right arm on fire during the Laver Cup tennis tournament at the O2 Arena in London
EPA
UK news in pictures 22 September 2022 Woody Woodmansey, Lee Bennett, Kevin Armstrong, Nick Moran and Clifford Slapper attend the unveiling of a stone for David Bowie on the Music Walk of Fame at Camden, north London
PA
UK news in pictures 21 September 2022 A flock of birds in the sky as the sun rises over Dungeness in Kent
PA
UK news in pictures 20 September 2022 Flowers which were laid by members of the public in tribute to Queen Elizabeth II at Hillsborough Castle in Northern Ireland are collected by the Hillsborough Gardening Team and volunteers to be replanted for those that can be saved or composted
PA
UK news in pictures 19 September 2022 The ceremonial procession of the coffin of Queen Elizabeth II travels down the long walk as it arrives at Windsor Castle for the committal service at St George’s Chapel
AFP/Getty
UK news in pictures 18 September 2022 A man stands among campers on The Mall ahead of the Queen’s funeral
Reuters
UK news in pictures 17 September 2022 Wolverhampton Wanderers’ Nathan Collins fouls Manchester City’s Jack Grealish leading to a red card. City went on to win the match at Molineux Stadium three goals to nil.
Action Images/Reuters
UK news in pictures 16 September 2022 Members of the public stand in the queue near Tower Bridge, and opposite the Tower of London, as they wait in line to pay their respects to the late Queen Elizabeth II, in London
AFP via Getty Images
UK news in pictures 15 September 2022 Members of the public in the queue on in Potters Fields Park, central London, as they wait to view Queen Elizabeth II lying in state ahead of her funeral on Monday
PA
UK news in pictures 14 September 2022 The first members of the public pay their respects as the vigil begins around the coffin of Queen Elizabeth II in Westminster Hall, London, where it will lie in state ahead of her funeral on Monday
PA
UK news in pictures 13 September 2022 Crowds cheer as King Charles III and Camilla, Queen Consort arrive for a visit to Hillsborough Castle
Getty
UK news in pictures 12 September 2022 Crowds line the Royal Mile, Edinburgh, as King Charles III joins a procession from the Palace of Holyroodhouse to St Giles’ Cathedral following the coffin of Queen Elizabeth II
Katielee Arrowsmith/SWNS
UK news in pictures 11 September 2022 Members of the Public pay their respects as the hearse carrying the coffin of Queen Elizabeth II, draped in the Royal Standard of Scotland, is driven through Ballater
AFP/Getty
UK news in pictures 10 September 2022 Britain's Prince William, Prince of Wales, Britain's Catherine, Princess of Wales, Britain's Prince Harry, Duke of Sussex, Britain's Meghan, Duchess of Sussex, wave at well-wishers on the Long walk at Windsor Castle
AFP/Getty
UK news in pictures 9 September 2022 King Charles III and Camilla, Queen Consort wave after viewing floral tributes to the late Queen Elizabeth II outside Buckingham Palace
Getty
UK news in pictures 8 September 2022 A screen commemorating Britain's Queen Elizabeth II in Piccadilly Circus, London Britain
EPA
UK news in pictures 7 September 2022 Police officers stand guard after Animal Rebellion activists threw paint on the walls and road outside the Houses of Parliament in protest, in London, Britain
Reuters
UK news in pictures 6 September 2022 Queen Elizabeth II welcomes Liz Truss during an audience at Balmoral, Scotland, where she invited the newly elected leader of the Conservative party to become Prime Minister and form a new government
PA
UK news in pictures 5 September 2022 Visitors at the PoliNations garden in Victoria Square, Birmingham, which is made up of five 40ft high tree installations and over 6,000 plants. The PoliNations programme aims to explore how migration and cross-pollination have shaped the UK’s gardens and culture
PA
UK news in pictures 4 September 2022 Undergraduates at the University of St Andrews take part in the traditional Pier Walk along the harbour walls of St Andrews before the start of the new academic year
PA
UK news in pictures 3 September 2022 The Massed Pipes and Drums parade during the Braemar Highland Gathering at the Princess Royal and Duke of Fife Memorial Park
PA
UK news in pictures 2 September 2022 Number 12 Company Irish Guards at Wellington Barracks, central London, before commencing their first Guard Mount at Buckingham Palace
PA
You can probably guess from the names that the latter is what actually matters – especially when inflation is so high and the gap between the two is so significant.
In a scenario where cash spending on public services is not increased by 10 per cent, they end up with higher costs due to rising prices, but their funding does not increase to match. So the cash does not go as far.
There are also other reasons to be sceptical. Due to demographic factors like an ageing population and simple population growth, some particularly expensive services like the NHS and social care require a real terms increase just to provide the same level of care to a larger number of people using the service.
So even if a real-terms increase is pledged in some areas, it may lead to a cut in funding per patient.
All this explains why the prime minister is happy to say there won't be any cuts to public spending. This does not mean there won't be austerity .
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies