EU Trade Commissioner Peter Mandelson has given support to the government's international development agenda.
Mr Mandelson urged the US to drop trade tariffs and quotas
Tony Blair and Chancellor Gordon Brown have promised that the developing world will be a top priority in 2005.
Mr Mandelson proposed an end to agricultural subsidies and said the US, EU, Japan and Canada should get rid of trade tariffs on poorer nations.
This year is a "once in a generation" chance for change, he told an audience at the London School of Economics.
"One can feel the gathering of international political will," he said.
The G7 meeting of finance ministers from the world's richest nations, including Mr Brown, is a "crucial milestone" for mobilising aid and tackling debt, Mr Mandelson added.
And he proposed a new focus on Economic Partnership Agreements between the EU and African, Caribbean and Pacific regions.
He said there should be better aid co-ordination between EU states.
Mr Mandelson told the audience: "I am encouraged that European leaders are rallying behind proposals for new financing and debt relief initiatives."
He said the World Trade Organisation, the EU and the G7 group could "take the power of the global trade agenda and put it in the service of development".
Mr Mandelson urged richer countries to abandon trade tariffs and quotas for designated poorer countries.
As well as reform of the EU's own system, he also urged the US, Japan and Canada to drop their tariffs and quotas.
He said the EU should help developing countries to meet health and consumer standards and new funds should be set up to invest in infrastructure.
Mr Mandelson resigned from Tony Blair's Cabinet in controversial circumstances on two occasions.
He became EU Trade Commissioner in 2004.