A majority of backbench MPs have signed an Early Day Motion calling for an acceleration of debt cancellation for developing countries.
Supporters of the Jubilee Debt Campaign and the World Development Movement (WDM) wrote letters and lobbied MPs personally to gain support for the motion, which has been signed by 282 MPs.
The motion calls on the Government to advocate faster debt cancellation at the spring meetings of the International Monetary Fund and World Bank from 20 to 22 April.
Beverly Duckworth, head of campaigns at WDM, said: "It is bad enough that the original promises of debt relief were inadequate, but the fact that only 15 per cent of the unpayable debt has been cancelled is a insult to the world's poor."
The Early Day Motion was tabled by Labour MP Julia Drown, chair of the All-Party Group on Third World Debt, and was sponsored by Labour, Liberal Democrat, Conservative and Plaid Cymru MPs.