The head of the World Bank said on Thursday he was fairly confident 20 of the world's poorest countries would be receiving extra debt relief by the end of this year.

The bank and its sister institution, the International Monetary Fund, are racing to meet the year-end target after the initiative aimed at easing the debts of the most heavily indebted poor countries (HIPC) moved more slowly than hoped.

James Wolfensohn, the bank's president, said he was "fairly confident, but not totally confident" that the target of 20 countries set by the Group of Seven industrialised countries could be met. "One thing I'm wholly confident about is that if we don't, it won't be the fault of the bank and the fund," he said.

Originally, 24 countries were targeted to receive debt relief by the year's end, but only 10 have so far done so. Lucy Matthew of the Jubilee 2000 coalition of debt campaigners said the end-year figure was still likely to fall short of the lower target, perhaps by three.

Mr Wolfensohn's claim suggests he views the blame as lying with borrowing governments that have not worked quickly enough on meeting conditions or with rich countries that have not provided the finance they promised.

Gerald Ssendaula, Uganda's finance minister, told Reuters yesterday that the country had seen its debt payments to rich countries and institutions fall by only half despite having met all the demanding criteria to qualify for large-scale debt relief.

Uganda has also received less debt relief than it was expecting from the Paris Club of creditor governments as Austria, backed by Germany, France, Italy and Japan, argued about the definition of what constituted debt under HIPC.

Mr Wolfensohn said that the heavily indebted poor countries would be left paying an average of 11 per cent of their government revenues in debt service payments after receiving relief - only slightly higher than the 10 per cent ceiling called for by many debt campaigners.

But Oxfam, the development campaigner, said this figure was misleading, based on savings over the next five years, and counting only the 10 countries that had so far passed the initial qualification stage for debt relief.

In the first three years after debt relief, countries such as Zambia, Cameroon and Malawi, which have yet to qualify for the first stage of relief, were likely to be paying over a quarter of their government revenues in debt service, Oxfam said.

The World Bank said analyses of countries yet to qualify for relief were "too preliminary to be useful".