Labour campaigners in London have issued a dire warning to Sir Keir Starmer over the state of the party in the capital, suggesting Zack Polanski's Greens and Nigel Farage's Reform UK will cause a "political earthquake." Officials have been privately circulating new data suggesting Labour could plummet from first to fourth place in London in the May elections. The data suggests Labour could lose flagship authorities, including Hackney and Lambeth, to the Green Party who would become the biggest party in London, reports The Guardian. Zack Polanski's party could also take Lewisham, Waltham Forest and Greenwich, as well as Wandsworth, Hammersmith & Fulham, Hounslow and Brent, if they were to run candidates in every ward. TRENDING Stories Videos Your Say The data was formulated using new technique, which builds on MRP modelling, using actual election results in the London along with polling data from Deltapoll, with an AI platform then predicting future voting behaviour over five years. Kemi Badenoch's Conservatives would go up from five councils to six, gaining Barnet with Reform UK winning Barking and Dagenham. However, Nigel Farage’s party would win 132 seats across London and be the largest party in Havering. According to the forecast from data firm Bombe, Labour would lose more than half its council seats, including in strongholds such as Camden, the location of Sir Keir Starmer's own Holborn and St Pancras seat. A Labour source told The Guardian: "A slow handclap for those self-appointed strategic geniuses who ridicule Labour values and think we can afford to sacrifice our core vote by mimicking the performative cruelty of Suella Braverman. "The dead end of McSweeney-ism must be abandoned before it’s too late. "When Labour focuses on the cost of living we can start to win back the progressive defectors we’ve lost and unite the coalition we need." A senior Labour London figure added: "It’s going to be a total catastrophe for us in London. If we lose swathes of voters on our progressive flank then we’re doomed. We need to start listening to them." LATEST DEVELOPMENTS WATCH: Andrew and Miriam baffled as Reform unveils 'major Labour defector' - 'Never heard of him!' Inside Reform’s battle for Sadiq Khan’s London — and the one stumbling block in Nigel Farage’s path to ‘Boris-style’ victory Local Elections 2026: Guide to key battlegrounds as over 5,000 seats up for grabs The data suggests Sir Keir Starmer's party could lose 741 seats across London. Zack Polanski's Greens would gain 530, the Tories 77 and the Liberal Democrats 72, as Labour continues to face pressure from all political fronts, as well as from pro-Gaza independents. Across London, nine other boroughs would go to no overall control, with the Greens the largest party in four, Labour in two and one each for Reform and the Tories. The Lib Dems and Labour would have the same number of seats in Southwark, while the Tories and Greens would in Westminster. Chief executive of Bombe Mike Joslin said: "Labour is facing wipeout in London in the face of a Green tidal wave. "The data shows that Labour’s core voters think Keir Starmer disagrees with them on Gaza, social equality issues and Brexit. They want someone that shares their values." One London Labour MP told the Guardian: "We can’t dismiss voters’ concerns and need to work hard to rebuild trust. We have some incredible Labour councils and councillors doing amazing work in their communities. "That work risks being undone if Labour nationally doesn’t start addressing worries of progressive voters around policies like welfare cuts, the language government uses on immigration and the response to Gaza." Our Standards: The GB News Editorial Charter