UN: World facing greatest humanitarian crisis since 1945

The world is facing its largest humanitarian crisis since 
1945, the United Nations says, issuing a plea for help to
 avoid "a catastrophe".

UN humanitarian chief Stephen O'Brien said that more 
than 20 million people faced the threat of starvation 
and famine in Yemen,Somalia, South Sudan and Nigeria.

Unicef has already warned 1.4m children could starve
 to death this year.

Mr O'Brien said $4.4bn (£3.6bn) was needed by July to
 avert disaster.

"We stand at a critical point in history," Mr O'Brien told
 the Security Council on Friday. "Already at the beginning 
of the year we are facing the largest humanitarian crisis 
since the creation of the United Nations."

"Now, more than 20 million people across four countries
 face starvation and famine. Without collective and coordinated global efforts, people will simply starve to  
death. Many more will sufferand die from disease.

"Children stunted and out of school. Livelihoods, futures 
and hope will be lost. Communities' resilience rapidly 
wilting away.

Development gains reversed. Many will be displaced 
and  will continue to move in search for survival, creating
 ever more instability across entire regions."

Mr O'Brien's comments follow on from a similar appeal 
made by UN Secretary General Antonio Guterres last
 month.

At that time, he revealed the UN had only received $90m (£74m) so far in 2017, despite generous pledges.

Like Mr O'Brien, he urged more financial support for the
 four countries. But why are they in such dire need?

The pictures were among the most shocking of last year:
emaciated children, clinging on to life with what little
 strength they had left. Four-year-olds not bigger than 
infants.

 And mothers unable to do anything to stop their children dying.

It is thought a child dies every 10 minutes in Yemen from
 a preventable disease, while half-a-million children under 
five are suffering from severe acute malnutrition.

The UN estimates some 19 million people - or two thirds 
of Yemen's population - is in need of some sort of humanitarian help following two years of war between 
Houthi insurgents and the government, which is backed
 by a Saudi-led coalition.

Continuing fighting, lack of rule of law, poor governance, under- development.

A naval embargo imposed by the Saudi-led coalition,
 fighting around the government-controlled port of Aden
 and air strikes on the rebel-held port of Hudaydah, have severely reduced imports since 2015.

A lack of fuel, coupled with insecurity and damage to
 markets and roads, have also prevented supplies from
 being distributed.

South Sudan

UN agencies say 100,000 people are facing starvation in South Sudan, while a further million are classified as being 
on the brink of famine.

It is the most acute of the present food emergencies, and 
the most widespread nationally.

Overall, says the UN, 4.9 million people - or 40% of South Sudan's population - are "in need of urgent food, agriculture and nutrition assistance".


Nigeria

The UN has described the unfolding disaster in north
-eastern Nigeria as the "greatest crisis on the continent" - 
the full extent of which has only been revealed as extremist militant group Boko Haram is pushed back.

It was already known the Islamist group had killed 15,000
 and pushed more than two million from their homes. But
 as they retreated, it became clear there were thousands
 more people living in famine-like conditions in urgent need 
of help.

The UN estimated in December there were 75,000 children
 at risk of starving to death. Another 7.1 million people in Nigeria and the neighbouring Lake Chad area are considered "severely food insecure".

What's hampering aid?

Boko Haram attacks, lack of rule of law, under-development.

There are still areas under the control of Boko Haram,
 which aid agencies cannot reach.

Thee have also been allegations of widespread aid theft, which are being investigated by Nigeria's senate.

Somalia

The last time a famine was declared in Somalia - just six 
years ago - nearly 260,000 people died.

At the beginning of March, there were reports of 110
 people dying in just one region in a 48-hour period.

Humanitarian groups fear this could be just the beginning: 
a lack of water - blamed partially on the El Nino weather phenomenon - has killed off livestock and crops, leaving 6.2 million people in urgent need of help.

What's hampering aid?

Continuing attacks by Islamist militant group al-Shabab, 
lack of rule of law, under-development.

Piracy off Somalia's coast impeded shipments in the
 past - however attacks have reduced significantly in recent years.