The Director of CAFOD, the Catholic Agency for Overseas Development, has written to Prime Minister Gordon Brown urging him to keep on driving forward the anti-poverty agenda on the global stage.

Chris Bain, head of CAFOD, said that poverty was one of the "most pressing international development issues of the moment".

He praised Mr Brown's commitment to the poor as Chancellor and appealed to him to maintain the same fervor as Prime Minister. It was particularly important, said Mr Bain, to continue leading international efforts to cancel debt to the world's poorest countries.

"Your continued leadership as Prime Minister on this issue is essential and will be strengthened if the Government accelerates its efforts to cancel UK debt to the 67 poorest countries as committed by you as Chancellor last year," he wrote.

2007 marks the 40th anniversary of Pope Paul VI's encyclical Populorum Progressio, or 'On the Development of Peoples'.

In the document, the Pope set out the Church's position on increasing poverty and injustice in the developing world, concluding that, "God intended the earth and everything in it for the use of all human beings and peoples."

"This still resonates and forty years later we still have a long way to go to achieve this," said Mr Bain.

He went on to urge Mr Brown to restore the UK's standing in the international community in light of its controversial invasion of Iraq with the US.

"With so many of the challenges facing the world's poor requiring action by the international community, I hope you are able to find ways to stem the leaking away of influence that has dogged the UK since the invasion of Iraq," he said.

"To do this requires your willingness and commitment to put global justice at the heart of wider UK foreign policy."

He called on the Government to set a year-by-year timetable to meet its target of 0.7 per cent GNI as aid and bring it forward to 2010.

"Progress on trade has been glacially slow, despite repeated campaign pledges to show leadership and put the interests of the poor at the centre of Government policy.

"A priority for you is to put real pressure on the European Commission to ensure that Europe's new trade relations with Africa do not lead to forced liberalisation of sectors of importance to poor people and the environment," he urged Mr Brown.

Mr Bain also warned that climate change poses an "overwhelming threat" to developing countries, "despite the fact they have not been responsible for creating it."

He welcomed the recent Government commitment to tackle climate change but said it would require "hard work" in international negotiations and a "toughening up" of the Climate Change Bill to include an 80 per cent reduction target for carbon emissions by 2050.