A severe famine is now spreading across many countries in West Africa following the devastating locust invasion last year and localised drought. Millions of people are facing food shortage in Niger, Senegal, Chad, Mali, Mauritania and Burkina Faso.

In response to the crisis, leading UK-based aid agencies have pledged millions in an appeal and urged the government to step up its aid commitment to West Africa.

Oxfam Great Britain launched a £1 million appeal for the West Africa Food Crisis on Thursday.

"The situation is desperate. Even the limited food that is available has soared in price rendering it unaffordable for most families and there is no hope of any harvest for at least three months. Families are feeding their children grass and leaves from the trees to keep them alive," said Natasha Kafoworola Quist, Oxfam’s Regional Director for West Africa, currently in Niger.

Oxfam experts in Niger are setting up a US$2 million food support programme. Vouchers will be distributed to 130,000 people which can be traded for food with local traders. Plans are also in place to help 28,000 nomadic herders to buy new animals for a fair price.

Niger is reported to be the worst affected country, 3.5 million people, which is one-third of the total population, are desperately in need of food aid. An estimated 150,000 children are facing acute malnutrition as well, according to the Christian Aid.

Aid agencies in the UK have unanimously blamed the international community for its slow reaction to deal with the deteriorating trouble in Niger.

World Vision's international programmes officer, Alex Whitney said, "The UN appealed for funds in May and was initially entirely ignored. Two months down the line they have declared that only a third of the $30m requested has been delivered."

"Less than a month ago the G8 leaders promised more and better aid for Africa," Whitney continued. "And now as 800,000 children under the age of five face a massive food crisis, the international community has failed to respond adequately."

Oxfam echoed that pledges that have been made have not translated into money arriving. Therefore, it is calling on the public to support its latest £1 million appeal.

World Vision warned the UK government to step up its aid commitment of £2m in order to help the people in Niger.

This year World Vision UK has committed almost US$1.5m (about £863,000) to programmes in Niger. While part of this money will respond to the emergency by funding nutrition programmes, World Vision UK also emphasised on long-term strategies to help Niger's government meet the needs of its own people.

The rest of the fund will be devoted to long-term recovery by working with communities to create fruit and vegetable gardens, cereal banks and food-for-work schemes. Over 2,600 malnourished children are expected to be fed by the World Vision over the next six months.

"It is vital that the international community act quickly," Whitney of World Vision added.

"Oxfam's programme is saving lives but in the face of the level of need, this is just a drop in the ocean. Almost four million people need food aid now. The UN appeals need immediate funding to ensure that all those in need receive help," Quist of Oxfam said.