OUR world can provide enough food for everyone, and yet one in every eight people on this planet goes to bed hungry. The problem is intensified because the rich of the world have found lucrative ways of using the assets of poor countries, stripping them of resources that are rightly theirs.

In two weeks' time, the G8 summit will be meeting in the golf resort of Lough Erne, in Northern Ireland. Because the UK is hosting this summit, it is a vital opportunity for our government to ensure that these issues of global morality and economics are fully on the agenda. The question is whether it has the courage and political will to bring change. Millions of people are hoping that it has.

More than 200 charities, including Christian NGOs such as CAFOD, Tearfund, and Christian Aid, have highlighted two crucial areas of unscrupulous exploitation that are exacerbating global poverty and increasing hunger. The first is tax-evasion (News, 17 May).

Tax revenue that should be going to poor countries from companies operating in them is being siphoned off. Quietly nestling in large financial centres, as well as in empty paradises, in places such as the Caribbean, tax havens provide the legal machinery to protect illegal tax-evaders, thereby depriving many struggling economies of the tax money that is desperately needed.

The Organisation for Economic Co-operation and Development (OECD) reports that developing economies lose three times more money in tax each year than they receive in aid. The fact that the UK is responsible for one in five of the world's tax havens puts an extra responsibility on our government to take a lead, and to end the secrecy of these havens. The very least we can ask is that it has the moral guts to ensure that such an abuse of power no longer lines the pockets of the rich, and cheats the poor of their entitlement.

The problems do not end with tax evasion. Unscrupulous companies and individuals can, and do, use their power dubiously to make other acquisitions. Global charities are urging the G8 also to address issues of "land-grabbing".

It is estimated that, every second, poor countries lose an area of land the size of a football pitch to private investors. In countries such as Sudan, Liberia, Cambodia, and Honduras, land that could grow food for local people is being bought by exporters, Wall Street speculators, and tourism-providers.

An Oxfam report says that more than 60 per cent of investments in agricultural land by foreign investors between 2000 and 2010 were in developing countries that have serious hunger problems: 63 per cent of the arable land in Cambodia went to private companies. But two-thirds of the investors planned to export everything they could produce on the land, often first leaving it idle so that its value increased.

Nearly 60 per cent of the deals were to grow crops for biofuels, bringing rich pickings for the already-rich speculators. The effect on those who live on the land has been disastrous. It no longer grows their food, and jobs, homes, and livelihoods have been taken - sometimes violently, and often without compensation.

The stark reality is that those with economic and political power can always override the poor. That is probably why Jesus warned that it is harder for a camel to go through the eye of a needle than for the rich to enter the Kingdom of God. Yet the G8 countries have both political-economic weight and legal jurisdiction. Christians across the world are urgently praying that they will use their power to bring justice to the poor, and righteousness closer.

Dr Elaine Storkey is President of Tearfund.