Nick Clegg will call on rich countries to follow Britain's lead in meeting targets for aid to the developing world by 2015 deadline.
The Deputy Prime Minister's call comes as he announces a boost of up to £350 million a year in British funding for action to beat the killer disease malaria.
Speaking at the UN Millennium Development Goals summit in New York, the Deputy Prime Minister will say that Britain will keep its promises on aid, and urge the rest of the international community to show "resolve" in doing the same.
While acknowledging demands for aid to be reduced to preserve money for public spending at home, Mr Clegg will insist that help for the poor world is in Britain's "enlightened self-interest", because it will promote global economic growth and help prevent the spread of extremism and terrorism.
The UK is one of only a few developed countries still on track to meet the commitments they made when the Millennium Development Goals - including eradicating extreme poverty and reducing infant mortality by two-thirds by 2015 - were agreed a decade ago.
Speaking on the final day of a three-day summit called to assess progress on the Goals, Mr Clegg will tell more than 140 prime ministers, presidents and monarchs from around the world: "My message to you today from the UK Government is this - We will keep our promises and we expect the rest of the international community to do the same."
