Rishi Sunak has urged voters to not hand Keir Starmer a “blank cheque” as he launched a Conservative manifesto that promised a series of tax cuts but contained little in the way of surprises. “Do not forget that Keir Starmer is asking you to hand him a blank cheque, when he hasn’t said what he’ll buy with it, or how much it’s going to cost you,” the prime minister said in a heavily Labour-focused speech at Silverstone racetrack in Northamptonshire. “If Labour win this time, they’ll change the rules so that they are in power for a very long time,” Sunak told an audience including his cabinet. He added: “So if you don’t know what Labour will do, don’t vote for them. If you’re concerned about what Starmer isn’t telling you, don’t vote for them. And if you’re worried about what Labour’s £2,094 of tax rises would mean for your family’s financial security, don’t vote for them.” The one new fiscal element in the manifesto, launched just before he spoke, was a pledge to entirely eliminate self-employed national insurance contributions (NICs), along with the widely trailed promise of a 2p cut from employee NICs, taking it down to 6p from April 2027. The manifesto added: “Our long-term ambition, when it is affordable to do so, is to keep cutting national insurance until it’s gone.” Other part-surprises including a beefed-up pledge on migration, in which Sunak said a government “will” halve net arrival numbers, and a promise to build 1.6m new homes over the course of the parliament. Abolishing self-employed NICs would be an incentive, Sunak said, for “the risk-takers, the people who graft hard to make a living who get our economy growing”. Other promised tax cuts had been briefed in advance, including cuts to stamp duty, increasing the threshold for receiving child benefit, and guaranteeing state pensions are not subject to income tax. Costings in the document said that by 2029-30, these would total over £17bn a year in total, the bulk of it to pay for a promised halving of employee national insurance rates. Another £2.6bn would cover the abolition of self-employed national insurance contributions. While Sunak said all these pledges were fully costed, by far the biggest increases in suggested government revenues come from two highly contested sources: a claimed £12bn saved by cutting back on social security payments, and £6bn on cracking down on tax avoidance and evasion. Other questionable promised savings include £1.2bn a year from “quango efficiencies” and £550m from cutting 5,500 NHS managers. One costings page in the manifesto suggested that increasing defence spending to 2.5% of GDP would cost £5.7bn a year by 2029-30 – and also claimed the state could save nearly £4bn a year by cutting civil service numbers. On green policies, the manifesto continued to push back against net zero commitments, with one policy including giving the Climate Change Committee, which advises the government on emissions, “an explicit mandate to consider costs to households and UK energy security in its future climate advice”. The manifesto also ruled out any future green levies on bills, or taxes on frequent flyers. There is a risk for Sunak that none of this will be enough to placate his more rightwing MPs, including any firmer commitments on the European convention on human rights (ECHR), and nothing further on tax, for example the possible abolition of inheritance tax. His language stayed the same on the ECHR, despite pressure from the Tory right to offer stronger hints that the party should pledge to leave if it created barriers in deporting asylum seekers to Rwanda. “If we are forced to choose between our security and the jurisdiction of a foreign court, including the ECHR, we will always choose our nation’s security,” he said. In a post-speech Q&A, Sunak was twice challenged as to why he had not been more bold, particularly on the ECHR, with one question suggesting this could be the solution to the Conservatives “haemorrhaging support to Nigel Farage”. Both times, Sunak refused to be drawn. Asked about deteriorating public services, Sunak said day-to-day spending would rise, while adding that it was “reasonable to look for efficiencies in the public sector”. Other elements of the manifesto also went less far than some expected. For example, the idea of a potential ban on smartphones for young people has ended up being a statutory bar on them being used in the school day, something most schools do already. Before details of the manifesto emerged, Starmer dismissed it as a product of “desperation” – and compared it to Labour’s policy-packed 2019 election offering, which he stood under. “The money’s not there for the Tories’ desperation,” Starmer said during a visit to a school in Middlesbrough when asked about the proposal to cut 2p more from national insurance. “They’re building this sort of Jeremy Corbyn-style manifesto, where anything you want can go in it, none of it is costed.”