HM Revenue and Customs has been sharply criticised by parliament’s spending watchdog for being unable to track how many billionaires pay tax in the UK. However, the government last week declined to rule out the introduction of a wealth tax after the former Labour leader Neil Kinnock called for a new levy to be introduced. The Treasury expects this to raise £7.5bn a year in extra tax by 2029-30 through helping to close the tax gap. However, the PAC report will add to pressure to ensure the wealthy contribute their fair share. A HMRC spokesperson said the extra resources announced in the spending review would allow tax officials to “significantly step up our work”.