The United Nations requested on Tuesday $ 21.9 billion to address 21 global humanitarian crises in 2019.
According Reuters $ 4 billion would be allocated to Yemen, noting that the appeal to donor countries did not include funding requirements in Syria.
It expected the total amount required by United Nations will encrease to 25 billion dollars.
Yemen is facing the world's worst humanitarian crisis, according to the UN, as more than 22 million people (more than two thirds of the population) are in need for a type of humanitarian aid and immediate protection, including 8.4 million people unsure how to get next meal, and some 2 million children suffering severe shortage of nutrition.
At a press conference on Tuesday, U.N. Under-Secretary-General for Humanitarian Affairs and Emergency Relief Coordinator Mark Lowcock, said Yemen's government will need billions of dollars in external support to finance its 2019 budget and avoid another currency collapse in addition to $4 billion in aid.
"There is going to be a need for billions of dollars of support so they can finance core functions of government.", Lowcock said.
"Unless they get some external finance for their budget these problems we saw with the rial plummeting will be back.", he said.
Lowcock said he discussed the balance of payments deficit and the need to pay Yemeni salaries and pensions with officials from Saudi Arabia, the United Arab Emirates and the United States in talks held in Riyadh on Saturday.
Yemen has been racked by armed conflict which broke out after the Iranian-backed Houthis had ousted the internationally recognized government in late 2014.
The Yemeni riyal has seen a frightening collapse in the last two months, falling to a record low against the dollar and foreign currencies amid continued high food prices, before improving last week following several measures taken by the internationally recognized government.
The financial situation has become more chaotic since President Hadi's government decided in September 2016 to relocate the central bank from Sanaa to Aden and appoint a new governor. The Houthis rejected the move, leading to two central rival banks operating in the country.
The confusion pushes many Yemenis in need of more than two years of unpaid salaries has left over one million employees, most of whom live in areas under the control of the Houthis, including the capital, Sanaa.
Yemen has suffered an unprecedented financial crisis since the Houthis seized control of the capital Sana'a and stopped oil exports for more than three years. Its revenues accounted for 70 percent of the country's revenues, as well as the suspension of customs duties, taxes, all foreign aid, foreign investment and tourism revenues, causing a poor state on the verge of collapse.
The conflict escalated after a Saudi-led military coalition intervened militarily in the country in March 2015.
The conflict escalated after a Saudi-led military coalition intervened militarily in the country in March 2015, to reinstall President Hadi and his government, and has left nearly 11,000 people dead, hundreds of thousands injured, 3 million displaced and made other thousands to flee the country.
The conflict in Yemen has killed more than 11,000 civilians, wounded tens of thousands, displaced three million people inside the country and fled thousands outside.