Rishi Sunak is plotting a new tax on online deliveries next month and a raid on the self-employed later this year, The Telegraph can reveal. The Chancellor will use Wednesday's Budget to announce a £5 billion fund to help high street pubs, restaurants and non-essential shops that have remained closed as a result of the Covid lockdown. On March 23 – dubbed "tax day" in Whitehall – he will then unveil a series of consultations on further tax increases to start paying for the £300 billion cost of dealing with the virus crisis. The Telegraph has learnt that this will include options to tax online retail more heavily, including the possibility of a new green tax on every internet delivery, alongside other online tax ideas. However, it is understood that he has turned his back on a mooted windfall tax on the "excess profits" of internet companies. Mr Sunak is also planning to use a Budget in the autumn to increase National Insurance Contributions paid by Britain's 4.5 million self-employed, arguing that they too benefited from state support in the pandemic. A Treasury source said: "The idea of an online sales tax is being looked at as part of the business rates review. "Responses to the consultation are being considered in the round, but the Chancellor is cognisant of the need to level up the playing field between the high street and online taxation."