The Treasury has lowered the level of the revenue it anticipates will be generated from the new 50 per cent income tax rate.
It doubts that it will receive its original estimate of £1.1 billion from the tax rate, according to city minister Lord Myners.
Speaking at the House of Lords he said: "We have made adjustments for the behavioural consequences of a new higher rate of taxation and accordingly have significantly reduced the anticipated tax take."
Lord Myners is also doubtful that the expected revenue of £2.5 billion will be generated from the tax rate either.
Although he still feels the tax rate will help revenues, Lord Myners recognises that some people have moved abroad due to the increase in taxation.
The House was reminded that the changes to the highest rate of taxation will affect less than two per cent of the working population.
High earners have been advised by private banks and wealth managers to act immediately to protect their income before the changes are made in April, the Financial Times reported.
