Self-employed workers will be able to apply for a grant of up to £2,500 a month to help them cope with the financial impact of coronavirus, the chancellor has announced.The money will be paid in a single lump sum, but will not begin to arrive until the start of June at the earliest.Rishi Sunak told the self-employed: "You have not been forgotten."Plans for 80% wage subsidies for staff kept on by employers were announced last week.The chancellor spoke after the total number of people in the UK to die with Covid-19, the disease caused by coronavirus, reached 475.