The UN warned Tuesday of a "severe increase" in Yemen's hunger rate and cautioned the situation would deteriorate further in 2019, when four million more people are expected to need food aid.
The head of the World Food Programme, David Beasley, told reporters that a food security survey due to be published later this week would show "a severe increase in hunger rate" in the country.
"We are seeing the severe hunger rate spike, from eight million to 12 million," he said, stressing that "these are the people who are on the brink of starvation... These are people who don't know where the next meal is coming from."
"This is not a country on the brink of catastrophe. This is a country that is in a catastrophe," Beasley said.
The UN humanitarian agency, OCHA, meanwhile listed the humanitarian crisis in Yemen as its top concern going forward.
"The country with the biggest problem in 2019 is going to be Yemen," OCHA chief Mark Lowcock told reporters in Geneva as he released the agency's projected global humanitarian needs assessment for next year.
He said that in 2017, the UN had provided food assistance to three million people a month in Yemen.
That figure rose to eight million per month this year and should hit 12 million in 2019, Lowcock added.
The numbers are devastating, but Beasley said it remained unclear if all conditions had been met for a full-fledged famine to be declared, according to the so-called Integrated Food Security Phase Classification (IPC) scale.
But, he stressed, "to me, it is bad. It is bad enough and we don't need to be waiting for it to be declared a famine."
"We need to be all hands on deck, because usually once a famine has been declared you are way behind the curve."
- Sent home to die -
Beasley described visiting a hospital in Sanaa recently, and seeing a tiny boy of eight, but who looked like he was five, lying limply in bed.
He said he tried to tickle his feet to get a smile, but "it was like tickling a ghost".
He was told that that hospital alone received around 50 children in the same condition each day, but only had the capacity to care for 20.
When he asked what happened to the other 30, the hospital administrator had told him: "We send them home to die."
"This is Yemen. This war must end," Beasley said.
The crisis in Yemen spiralled after a Saudi-led coalition launched an offensive to support the government against Iran-backed Houthi rebels in March 2015.
The situation has worsened in recent months due to a broad economic collapse and rising violence in the rebel-held port of Hodeida, a crucial import hub for food and other basic supplies.
Lowcock said the UN as a whole is asking for $4.0 billion (3.5 billion euros) to help suffering Yemenis next year. Beasley said WFP alone needs around $160 million each month just to cover the most desperate food needs.
Overall, 24 million people in Yemen -- roughly 75 percent of the population -- will need humanitarian assistance in 2019.
Lowcock noted that the government will also need additional budget support from other countries to pay salaries and pensions in order to contain wider suffering.
He indicated that some of Yemen's allies in the Gulf, notably Saudi Arabia, have committed to continue helping finance the government.
The OCHA chief stressed, however, that the outlook for Yemen could improve if progress is made at UN-brokered peace talks, set to begin in Sweden this month.
If the talks show results, "it is possible that we could find by the second half of the year that the extreme edge could get taken off the suffering of those people who have no form of income," Lowcock said, while noting that diplomatic gains were difficult to predict.