More than 600,000 people – many of whom became self-employed in 2019/20 – are estimated to now be eligible for cash grants.
Ahead of the Budget, Mr Sunak said: “Our Covid support schemes have been a lifeline to millions, protecting jobs and incomes across the UK.
“There’s now light at the end of the tunnel with a roadmap for reopening, so it’s only right that we continue to help business and individuals through the challenging months ahead – and beyond.”