UNICEF warns that the number of 18.5 million people who are unsure of where their next meal is coming from may soon dramatically increase.
The United Nations children's agency says Yemen's economic crisis and the relentless violence at a key Red Sea port city risks leaving millions of children and families without food, clean water and sanitation.
UNICEF says water and sewage services face the risk of collapse due soaring fuel prices affected by the local currency plunge.
It warned in Thursday's statement that families are unable to afford basic food items and that the number of 18.5 million people who are unsure of where their next meal is coming from may soon dramatically increase.
The agency also says the violence in the port city of Hodeida threatens choking off essential aid.
Yemen's war has been raging for more than three years, spawning what the UN says is the world's worst humanitarian crisis.
The three-year conflict between Yemen's Saudi-backed government and Houthi rebels linked to Iran has left more than 16,000 civilian casualties most of whom were children.