The very rich have grown richer at double the pace of most Britons under Labour and their incomes may have accelerated even further in recent years on the back of a rising stock market, research from the Institute for Fiscal Studies shows.

Using the most detailed analysis of tax return records to date, the think-tank showed that, in every 1,000 adults, the income of the very richest person rose on average by 4 per cent above inflation every year between 1996-97 and 2004-05. That compared with growth of about 2 per cent for those on middle incomes.