Funding requirements next year will amount to $21.9bn with Yemen facing the worst humanitarian emergency followed by Afghanistan, Cameroon and the Central African Republic.
Presenting the Global Humanitarian Overview for 2019, Emergency Relief Coordinator Mark Lowcock said the UN and its partner organisations aim to assist some 93.6 million of the most vulnerable with food, shelter, healthcare, emergency education, protection and other basic assistance in 2019.
"Most of the humanitarian crises we have seen in 2018 will continue into 2019 because there has been little progress in addressing the root causes," Lowcock said while addressing the media in Geneva.
"We need to make it a bigger priority to address the underlying causes: Conflicts, poverty, climate change, food insecurity, development programmes' failure," he said.
Lowcock said the figure of $21.9bn needed for 2019 does not include the financial requirements for Syria, which will be confirmed upon finalisation of the 2019 Syria Humanitarian Response Plan in February.
He said it is expected total requirements, including those for Syria, will be comparable to current requirements of about $25bn.
Humanitarian funding has increased if compared to previous years, with donors providing a record $13.9bn as of mid-November 2018 - about 10 percent more than at the same time in 2017, which was itself a record.
The UN official said the UN response will have to deal with a higher rate of displacement and increasing food insecurity than in the past.
Nearly 70 million people are displaced by conflict, more than ever before, Lowcock said. In addition, crises are exacerbating gender inequality with girls more likely to drop out of schools in areas affected by humanitarian emergencies.