DW: The UN says over 20 million Yemenis out of a population 28 million are in need of help. Seven million — one quarter of the entire population — suffers from extreme hunger. Millions have fallen ill with diphtheria or cholera. Earlier this year, you traveled to Yemen yourself. Tell us what you experienced.

Karl-Otto Zentel: The country bears the marks of three years of civil war. The private sector has collapsed, as has the state [sector]. Public servants haven't been paid in months. Families have used up their savings. And certain rural traditions are no longer practiced: Inside the villages I was told by men that they used to head to Saudi Arabia for three or four months to work. The money they earned there and the money made at home from selling agricultural produce used to suffice to the feed the family. But now, they can no longer go to Saudi Arabia because the border is closed. Trying to cross it is very dangerous.

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Two million people are internally displaced. Many have moved in with relatives in the cities. A colleague of mine told me that half a year ago, his salary was enough to feed his own family. Now, his salary has to feed seven families.

One of the reasons why people are suffering is because a US-backed, Saudi-led military coalition has imposed a blockade. Aid deliveries, food deliveries, fuel, medicine — none of this is getting through to northern Yemen. How does this affect the work of your humanitarian agency?

Yemen always needed to import 80 to 90 percent of its basic food staples. Most of this food was imported via sea, some of it by land via Saudi Arabia. The country's major ports that were used for these imports lie in the north — which is controlled by Houthi rebels. These ports are blocked. Consequently, there is less food inside the country, prices are rising, and so less and less food is available to the Yemeni people.

The country has been under a total blockade since early November. That means not even aid deliveries are getting in. That has a dramatic effect on our work. For example: Chlorine tablets that are needed to treat drinking water are almost depleted. This increases the risk of cholera spreading even further. We are running low on much need vaccines. Measles and other diseases could spread even more. We're already in a situation where every 10 minutes a Yemeni child dies of a preventable disease. For example from diarrhea, malnutrition or respiratory disease.

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Is it time for the international community to exert greater pressure, for instance on Saudi Arabia, to at least lift its blockade of Yemeni ports and to open the border?

Yes, much more international pressure is need. The situation in Yemen is not receiving the kind of attention it should. That also explains why there is little international pressure. The conflict resolution mechanisms we have have on the international level have not brought peace to Yemen.

As a humanitarian agency you need to prepare for different outcomes. What is the best-case scenario for Yemen?

Ideally, there will be peace. A peace agreement in the near future, signed by all parties, is necessary for the country to fully recover in the long-term.

How realistic is that?

Currently, I don't think it's realistic. It looks like this dire situation will persist. The world isn't paying enough attention to the Yemen conflict. That's why there's little international pressure. And the conflicting parties haven't yet reached a point were they're ready to talk. At least not to the extent one would hope for.

Has the violent death of former Yemeni President Ali Abdullah Saleh, who pulled the strings behind the scenes, further complicated the search for peace?

For a short period, Saleh's death made things more difficult for me and my colleagues working for CARE. Fighting began in Sanaa in early December. Clashes are taking place in provincial capitals, which are also heavily bombed from the air. This meant we had to reduce or halt our activities. Fortunately, my colleagues are all in good health. But we were quite limited in our activities for a certain period. We could not tend to important areas, like the water sector. This has made the country's humanitarian situation even worse.

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In early 2017, a large donor conference was held for Yemen. This generated substantial funds. Which was great. But the estimates made then no longer reflect the current status-quo. Back then, there was no cholera epidemic. Today, we have about half a million suspected cases and over 2,000 Cholera deaths. And those are the numbers we know. It is possible that there are further cases in other parts of the country which we don't yet know of. And because the blockade has drastically driven up food prices, our estimates for how much support a family needs to survive are no longer accurate. That means more help is needed. Every donation towards humanitarian organizations is welcome.

Karl-Otto Zentel is the acting general secretary of CARE Germany-Luxemburg. His humanitarian agency is engaged in Yemen to help alleviate the human suffering.