The tenth anniversary edition of the United Nations Human Development Report, which ranks countries according to their level of economic and social development, describes the growing gap as "grotesque" and calls for urgent action to make the world a fairer place.
A special message from Ted Turner, the media mogul who donated $1bn (pounds 602m) to the UN last year, echoes the report's demand for poverty reduction. "It is as if globalisation is in fast forward and the world's ability to react to it is in slow motion," he writes.
Other figures show that the world's richest 200 (Mr Turner is 38th) have more than doubled their wealth in the four years to 1998, to more than one trillion dollars (pounds 602bn). The 20 per cent of the world's population that lives in developed countries enjoy 86 per cent of the income.
The figures in this year's report show the UK climbing from 14th to 10th in the human development ranking, which incorporates life expectancy, literacy and educational indicators as well as the more conventional GDP per head. The improvement, reflecting figures up to 1997, is due mainly to increasing enrolment in higher education.
However, the UK fares worse on indicators of poverty. A high proportion of the population living on less than 50 per cent of median income and a high proportion unable to read and write well enough to function take it to number 15 in the poverty rankings.
Canada, Norway and the US top the human development table, as they did in 1998. At the bottom of the table, dominated by sub-Saharan Africa, lie Sierra Leone, Niger and Ethiopia.
A chapter on technology highlights the unequal spread of new technologies such as the Internet and biotechnology. Only in the richest countries is Internet access widespread, and even there it is mainly a white, male, upper-income group phenomenon.
Basic phone connections are rare outside big cities in the developing world, and can be poor in the rainy season. Thailand has more mobile phones than all of Africa. The Human Development Report is highly critical of the international rules that have allowed western multinationals to corner intellectual property rights and patents. This is allowing corporations to hijack traditional remedies. For example, two researchers at the University of Mississippi were granted a US patent for using turmeric to heal wounds, a practice which had been common knowledge in India for thousands of years. The patent was eventually repealed thanks to evidence provided by an ancient Sanskrit text. The exploitation of traditional knowledge has created a new skill: "bioprospecting". A few firms have agreed to pay royalties to countries on sales of drugs successfully derived from indigenous materials.
Some multinationals are praised for their good global citizenship. For example, Mattel, the Disney organisation and Nike are singled out in the document for improving working conditions and pay in their Asian factories.
The report, to be formally launched in London today by Clare Short, the Secretary of State for International Development, says such voluntary action will not be enough and pleads for "a rewriting of the rules of globalisation".
Its action plan includes controversial proposals for new international organisations such as a global central bank in addition to the IMF and a world investment trust that could redistribute incomes globally. It also urges a "bit tax" on Internet use to generate finance for the spread of new technology.
However, Mark Malloch Brown, the administrator of the UN Development Programme, takes issue with the report's findings. In a foreword he emphasises the need to make existing institutions work better and says markets must remain the "central organising principle of global economic life".
The Widening Gap: Main Points of the UN Report
n The three richest people in the world, Bill Gates, Warren Buffett and Paul Allen, have total assets - $156bn, according to Forbes magazine - greater than the combined GNP of the 43 least developed countries. More than 600 million live in these mainly sub-Saharan African states.
n The number of computers connected to the Internet was 36 million in 1998; ten years earlier it was 100,000.
n A Bangladeshi would have to save all of his wages for eight years to buy a computer; an American needs only one month's salary.
n Of all the patents in the world, 97 per cent are held by industrialised countries.
n Organised crime syndicates are estimated to gross 15 trillion dollars (nine trillion pounds) a year.
n More than 80 countries have a lower per capita income today than a decade ago.
n Of all the new HIV infections, 95 per cent happen in developing nations. World-wide, 16,000 people are infected every day.
n Half of the $30bn (pounds 18bn) that was grossed by Hollywood films in 1997 was taken at box offices outside the United States.
n Each day one-and-a-half trillion dollars (pounds 900bn) flows through the world's currency markets.
n The number of telephones per 100 people in Cambodia is one; in Monaco it is 99.
n Tanzania spends nine times more on repaying debts than on health care and four times more than it spends on education.