Drastic food price hikes coupled with swelling numbers of hungry people have caused some leading relief agencies to fear having to turn away those desperate for help.

The current global food crisis, dubbed by some as the "silent tsunami", has made food now unaffordable for those previously living on the fringe of poverty.

According to statistics from the UN Food and Agriculture Organisations (FAO), the international price for rice increased by 74 per cent, vegetable oils by 60 per cent, dairy products by 83 per cent, soybeans by 87 per cent, and wheat by 130 per cent.

In late April, the Economic Commission for Latin America and the Caribbean (ECLAC) warned that "the steep and persistent rise in international food prices is hitting particularly hard on the poorest in Latin America and the Caribbean".

At a recent Latin America presidential summit focused on the food crisis, Cuban vice president Esteban Lazo said his country paid about $250 for a tonne of imported rice in 2005, but it now costs the government $1,050 - or four times as much, according to Inter Press Service.

"Hunger continues to grow and the people are becoming increasingly desperate," wrote Food for the Poor, one of the largest relief groups working in Haiti, in a recent update.

Food for the Poor is a Christian charity that feeds nearly 20,000 people daily in Haiti and works in other Latin America and Caribbean countries.

"People think I'm joking when I ask them to search under cushions for loose change," said FFP executive director Angel Aloma, in a statement. "But with such a huge jump in the prices of food staples and transportation costs, we're looking for all the help we can get to keep up with the need in Haiti - no matter how small."

An estimated 80 per cent of people in Haiti live in abject poverty, and most struggle to get by on less than $2 a day. Haiti is the poorest country in the Americas.

Aloma says the skyrocketing cost of food means more Haitians are going hungry and that Food for the Poor needs more donations to keep up with the demand.

"Last year we sent an average of 880,000 pounds of rice to Haiti every month," Aloma says. "This year, we're sending 1,763,000 pounds and it is a real challenge to keep up with the increased demand."

Haiti president Rene Preval called what's happening in his country due to food shortages a "catastrophe", according to IPS. The food crisis has led to violence and protests that have left at least six people dead and several injured, as well as damages to shops as a result of looting in Haiti.

In addition to FFP, World Vision - one of the largest humanitarian organisations in the world - is also struggling to feed the world's poor. Last month, it announced that it is cutting back the number of people it can feed because of the economic slowdown.

Likewise, The Salvation Army in the US also complained about the economic slump and said its donations have been down whilst the needs have increased - Salvation Army shelters have been fuller recently, it noted.

In response, the US-based Christian group Bread for the World, has launched a campaign called Recipe for Hope that began on the US Mother's Day, May 11, and will run until the US Father's Day on June 15. The campaign seeks to mobilise people of faith in the US to "turn the recipe for despair into a recipe of hope" for mothers and fathers struggling to feed their families.

"As Jesus reminds us, when we share our bread with those who are hungry, God blesses even our smallest efforts," said the Rev David Beckmann, president of Bread for the World. "Feeding the hungry is itself an act of worship."

The World Bank estimates that as many as 100 million people will join the ranks of 854 million poor and hungry people who currently do not have enough to eat each day.