More than a million malnourished children aged under five in Yemen are living in areas with high levels of cholera.
The war in Yemen has created one of the world's worst humanitarian crisis as a pro-government coalition led by Saudi Arabia has been fighting Houthi rebels for more than two years.
The Houthis' rebellion culminated in 2015 when they took over the capital, Sanaa, with Iran's backing.
Months later, Saudi Arabia and its Arab allies entered the conflict.
Also, a cholera outbreak has also killed nearly 2,000 people and infected more than 400,000 in the country.
"You see cholera spreading because of attacks on health infrastructure, on electricity, on water distribution system [and] because of unclean water and we have to deal with this crisis in a comprehensive issue," said Peter Maurer, the president of International Committee of the Red Cross.
"And this is a very serious situation. It is the direct consequence of war."
More than a million malnourished children aged under five in Yemen are living in areas with high levels of cholera, the charity Save The Children says.
"My message to all international and local organisations is to give attention to people affected by the disease, because sometimes the pain is unbearable and cannot be tolerated. This disease is extremely dangerous," said Saleh Hudaif, a patient of cholera.
The warring parties have promised to let aid through after donors in Geneva pledged more than $1 billion dollars this year.
But Auke Lootsma, Yemen country director of UNDP said "we still require these funds to come through. We call on the international community to redouble their efforts to support the people of Yemen.
"If you fail to do so the catastrophe that we see unfolding before our eyes will continue to claim lives and will affect many generations to come."
TRT World's Rahul Radhakrishnan reports.