The warning comes as finance Minister Rachel Reeves is expected to announce sweeping fiscal changes in her upcoming budget, aimed at closing a multi-billion funding gap in public finances. The government is also planning to increase capital gains tax on shares and other assets by "several percentage points," according to reports. Additionally, the business asset disposal relief (BADR) scheme, which allows entrepreneurs to pay a reduced 10% tax on profits from the sale of their firms, is set to be cut.