After cutting national insurance for the second time in yesterday's Budget, the prime minister has said it's his "long-term ambition" to eventually scrap the tax.As only those in work pay it, it's seen by many – including the Chancellor - as an unfair double tax on those in the workforce. But, completely abolishing it would cost the government £46bn.Labour have criticised the plans, saying the move would cost more than the cuts unveiled in Liz Truss' chaotic mini-budget and the director of the Institute of Fiscal Studies called it unrealistic.On this edition of the Sky News Daily, Niall Paterson is joined by Greg Thwaites from the Resolution Foundation and Linda Yueh, broadcaster and economist, to explore how realistic scrapping NI would be and why it's so tricky to simplify the tax system.And, political editor Beth Rigby pops in to discuss how this idea is playing out politically. Producer: Sydney Pead Assistant producer: Iona Brunker Interviews producer: Melissa Tutesigensi-Charles Promotion Producer: David Chipakupaku Editor: Wendy Parker