Chancellor Rachel Reeves is fearing one date in 2025 more than anything else, economists have revealed in a damning warning to Labour. The party is battling to prove its economic plan is working in the wake of financial market turmoil that has seen the interest the government pays on its national debt rise to a thirty-year high. This means the government is paying more to service its debt and will find it harder to borrow more money, ultimately leading to less cash for public services. Reeves wants to borrow £30billion to pay for massive public spending increases set out in her budget.As a result, the Treasury has warned Labour to be ‘ruthless’ in identifying public spending cuts in an effort to save cash.One leaked internal letter from Number 11 also warned ‘difficult decisions’ were going to have to be made on Reeves’ budget. Gloomy economic developments hardly help a Labour government already slipping in the polls, but now a crucial date has emerged that could finish the party off for good. On March 26, the Office for Budget Responsibility (OBR)- Britain’s independent financial watchdog- will publish its Spring Forecast. The watchdog could find that with debt repayments costs spiralling, there is little to no room for the increased borrowing and spending set out by Reeves in her October budget.Without growth and the subsequently larger tax receipts, the government could be forced to row back on Reeves’ tax crusade in what would be an embarrassing reversal akin to Truss’ disastrous mini budget. Rupert Harrison, former chief of staff to George Osborne, said: “The Treasury will be nervously waiting for the official March forecast. “If that shows that the Chancellor’s already thin headroom against her fiscal rules has been eaten up by higher interest payments then she will have to cut her spending plans just five months after the Budget. “Her decision to increase borrowing by £30 billion a year is looking increasingly reckless. “An economic strategy born out of the zero-interest rate decade is totally inappropriate for the new world we’re in.”LATEST FROM MEMBERSHIP:MAPPED: The foreign farmers handed £500m in aid as Reeves slaps inheritance tax on local producers’An evil in society – war is not won’, warns bank worker who won unfair dismissal case over ‘N-word’Bank of England diversity drive sparks backlash: ‘No finance background? No problem’What could happen if the OBR forecast is poor? Markets often operate like a popularity contest, with investors deciding which country is the most attractive to invest in or lend money to. In 2025, Donald Trump’s America appears to be in pole position, with Europe and Britain lagging behind. If the OBR confirms this with a gloomy forecast, Labour may be forced to roll out an emergency mini budget cancelling some of Reeves’ measures in an attempt to win back confidence. One measure that could be watered down is Reeves’ raising of Employers’ NI contributions; a policy set to rake in a whopping £24billion. The move has led to many firms putting the brakes on expansion as the cost of hiring staff shot up. Another measure that could be rowed back on is Reeves’ changes to inheritance tax, namely the capping of Business Property Relief and Agricultural Property Relief. Family businesses previously enjoyed inheritance tax exemptions when a death occurred, but under proposed rules they will be taxed at 20 per cent on assets over £1million. Business leaders have slammed the measure, saying they have cancelled plans to invest and expand their business as inheritance tax bills threaten to wipe out profits.They feel particularly hard done by as they are competing with faceless mega corporations based abroad that won’t have to pay a huge tax bill every forty or so years.Similarly, Reeves’ inheritance tax on farmers- one of Labour’s most unpopular decisions- could be reversed in an attempt to win back some confidence in Britain’s agricultural sector.The industry is currently deeply unpopular to investors and bank lenders. 17 per cent of farms fail to make a profit in 2023, before Reeves’ punishing inheritance tax was even announced.The bigger pictureWatering down these measures would destroy Reeves’ credibility and seriously damage her chances of continuing as Chancellor. It would also be a major blow to Prime Minister Keir Starmer, who said “economic stability is the first step when it comes to growth of our economy” immediately after his election win.Both Labour figures have seen their popularity crash in recent months for a string of unpopular decisions.Politically, the Conservatives- historically more trusted on the economy- are set to gain, as well as Reform whose newcomer status means they have no history of poor economic management.Commentators have argued the situation is recoverable but have also pointed out the fact markets are more powerful than any politician. Economic woes have ousted droves of capable leaders throughout history. On March 26, Britain will see if Reeves and Starmer may join that list.