The United Nations is calling for urgent aid for Somalia to avert a catastrophe worse than the famine that claimed 260,000 in 2011.

UN Secretary-General Antonio Guterres, who visited the country on Tuesday — his first field trip since he took office in January — said the situation in the country was both tragic and regrettable.

"It's impossible to describe. It's the suffering of the people, every single person we have seen had a personal story of tremendous suffering. There's no way to describe it," he told journalists at Liiban camp in Baidoa after meeting the internally displaced people.

The UN chief later visited cholera patients and severely malnourished children at Bay Regional Hospital.

Cholera has so far claimed the lives of 25 people at the hospital. Seventy-three cholera patients were admitted at the hospital, while 2,340 were being treated as outpatients.

Earlier, Mr Guterres met with Somalia's President Mohammed Abdullahi Farmajo in Mogadishu and appealed for $825 million humanitarian support for the country.

"The combination of drought, conflict and disease outbreak calls for massive support," Mr Guterres said.

President Farmajo said his first priority was to address the drought crisis to avert a famine.

"Second is to deal with the security situation. Al-Shabaab and other terrorists organisations are an impediment to progress. We need to rebuild the Somalia National Army," he said.

More than a half of Somalia's population is in need of food aid. This is further complicated by insecurity as humanitarian agencies cannot reach the affected people.

About 200,000 people have moved to makeshift camps.

The UN requires $825 million for life-saving initiatives between March and June this year.

READ: UN chief Antonio Guterres in Somalia, appeals for $825m

"It makes me feel extremely unhappy. With the amount of wealth in the world, that such scenes are still possible," he said at the IDP camp.

In 2011/12, famine resulted in the death of 260,000 people in what was blamed on slow response from humanitarian agencies.

This time, the UN said agencies and the government were better organised to respond much faster.

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