The overall number of people in need of food assistance is expected to rise to 3.5 million by December, up from at least 2.6 million now, according to the WFP.
About 90 per cent of food aid arrives in Somalia by sea.
"Somalia is at a dire crossroads," Goossens said.
"If sufficient food and other humanitarian assistance cannot be scaled up in the coming months, parts of the country could well be in the grips of disaster similar to the 1992-1993 famine."
Abdi Awaleh Jama, ambassador for Somalia's transitional government, said that the country's administration was poorly equipped to deal with attacks on aid agencies and non-governmental organisations.
"Those who are attacking the [aid workers] are the enemies of the Somali government. Of course they are going to be the winner; the losers will be the affected population of Somalia. The international community should not allow that to happen," he told Al Jazeera.
"The only viable solution would be for these aid workers to regroup where the government forces are ... in the areas which [the government forces] control.
"We call on the international community to accelerate the deployment of United Nations peacekeeping forces in Somalia as soon as possible to avert a disaster."
UN under attack
Earlier this week the UN issued fresh protests about the security situation in Somalia after a transport agent working for the WFP was killed.
|THE WFP warns Somalia could face a famine as bad as that of 1992-1993 [File: EPA]
The man, who was shot in southern Somalia on Sunday, was the fifth WFP-contracted worker and the twelfth aid worker to be killed in the country this year.
Aid groups have scaled down operations because of increased security threats, largely blamed on fighters from the Union of Islamic Courts, which has waged a guerrilla war since they were ousted by joint Somali-Ethiopian forces in early 2007.
A desert nation of up to 10 million people, Somalia has been ravaged by war since Mohamed Siad Barre, the former president, was forced from power in 1991.
A ceasefire came into force on July 9 between the UN-backed interim government and opposition forces but has repeatedly been violated.
The latest violence occurred recently when an army camp in Mogadishu came under attack, triggering clashes that claimed the lives of four civilians.