Raphael Tuju, Kenya's foreign minister, told the UN General Assembly: "Somalia is almost dying. We can see it. We have known that for the last 16 years. This is the time to send in life-saving support.
"Humanitarian intervention now will yield better and faster results than a military intervention, and at a much cheaper price than sending troops to pursue criminal elements in a failed state."
Somalia has not had an effective government since early 1991, when faction commanders overthrew Mohamed Siad Barre and then fought each other.
A UN-backed interim government was formed in Kenya in 2004, the 14th attempt at effective central rule since 1991. But the interim government has been unable to extend its control beyond a single area - the small southern provincial town of Baidoa.
In the meantime, Somali Islamists have rapidly expanded their presence in the country since capturing the capital Mogadishu in June, defeating a coalition of self-proclaimed anti-terrorist commanders said to be backed by the US and leaving the interim government increasingly isolated.
Tuju said: "The comfort zone is to look at Somalia as being far away and hope that the problem will resolve itself somehow."
He added that a Somalia, with no government in place "is a danger not just to neighbouring countries but to the whole world".
While it was important for the interim government to keep up a dialogue with the Islamists, it was also important for other countries to step up support for the interim authorities, he said.
Addressing the General Assembly later in the day, Ismail Hurre Bubar, the transitional government foreign minister, said that because of the slow world response to Somalia's woes, "a window of opportunity has been lost", fueling the current conflict.
While his government planned to keep talking to the Islamists for now, this would not continue if they persisted in "their aggressive policies of attacks and territorial expansion", Hurre said.
Through a regional group known as the Intergovernmental Authority on Development (IGAD) Kenya has been pushing for the deployment in Somalia of an African peacekeeping force.
As part of the plan, IGAD - grouping Djibouti, Eritrea, Ethiopia, Kenya, Sudan and Uganda as well as Somalia - has asked the UN Security Council to partially lift an arms embargo on Somalia so the interim government could build up its security forces and invite in the African peacekeepers.
Tuju called for an international support group to coordinate the campaign, including the IGAD countries, the African Union, the Arab League, the European Union, the United Nations and one or two of the UN Security Council's five permanent members - the United States, Britain, China, France and Russia.
The Arab League has already endorsed the plan, Tuju said.