Rarely can so much bonhomie have been generated by a Monday morning trip on the Northern line. As the £1.1bn London Underground extension opened for the first time, the transport secretary, Grant Shapps, and London mayor, Sadiq Khan, rode west together to Battersea Power Station – and talked up the teamwork for a project that has finally come in under budget and on time. Services started at 5.28am, with enthusiasts queueing outside the new Battersea Power Station tube station for a slice of underground history, the first new stations this side of the millennium. Some were racing from the other end: a man with a homemade “first passenger for Battersea from Mill Hill East” sign stapled to his T-shirt jostled for position in camera shot when the VIPs arrived. How many residents of the new Battersea Power Station will be catching a morning tube remains to be seen, with multimillion penthouses still on sale and the cheapest of the 254 flats costing north of £800,000. But the redevelopment, with its riverfront picnic tables, entertainment venues and swanky boutiques already in place, and Apple’s HQ and the main power station conversion to come next year, will surely soon be luring more passengers down. The thorny question remains of how London will fund its transport system, with only a fraction of the fare revenue coming in since the coronavirus outbreak. While train and bus operators outside London have had the loss of their spiralling fares underwritten by the Treasury, the government has been decidedly less forthcoming in helping a Labour mayor who kept fares down. The funding crisis has been exacerbated by delays to Crossrail, the new east-west line, which is due to eventually open next year as the Elizabeth line. Khan, certainly, was hoping that some valuable lessons would be drummed into Shapps, with the current funding agreement for Transport for London set to expire in December, and talks ongoing on how to secure London’s financial base. “It’s got to be a long-term deal and we’ve got to change the funding model,” the mayor said. “On a formula where we have got to have 72% of our services paid for by fares coming in, it’s not sustainable. Before the pandemic we had 4m tube journeys a day – we’re nowhere near there.” He was keen, he said, to get Shapps to the opening of Northern line extension “to show the difference the government working with City Hall, public sector, private sector, can make. A London recovery benefits the national recovery. Every £1 you spend here, 55p is spent elsewhere in the country.” Shapps, though, was drawing other lessons, tweeting a photo of himself and Khan in full power pose under the “Power” on the station nameplate, announcing: “Thanks to government funding, two brand-new tube stations opened …” This may have been news to TfL, and especially the Greater London Authority and developers, who picked up the other 90% of the tab with loans to be funded by future increased business levies. Having claimed the credit, Shapps was at pains to say that far more money was being spent “levelling up” the north: about £29bn on transport since 2010, he claimed. On a more conciliatory note, he added: “We have to look after the capital as well, we’re committed to doing that, and today’s a great example of different groups coming together in partnership and doing something really great.” Nonetheless, the transport secretary warned: “TfL will have to take, and has had to take, some very difficult decisions in order to make sure the finances stack up. The government’s put in, I think, £4.1bn so far and counting. We’re going to have further conversations with them …. We have to expect TfL to make adjustments.” But standing in front of the gleaming Battersea station, serenaded by a community choir, that unpleasantness could wait. “Look, today’s a day when we got together and built something worthwhile for Londoners,” Shapps said. “We should stick on that positive note for today.”