Tube fares will have to rise by at least 4.6 per cent next year, the Government has told Sadiq Khan.Transport Secretary Louise Haigh has made a fares hike a condition of the £485m deal announced for Transport for London in Wednesday’s Budget.She told the mayor that he was expected to ensure that “TfL rail fares rise in line with national rail fares this year”.Despite mentioning only “TfL rail fares”, this is almost certain to apply across the Tube, London Overground and Elizabeth line services, due to all being part of the capital’s zone-based fares system.