The summit, co-organised by Jordan, Sweden, and Egypt in the Italian capital, convened on Thursday at the headquarters of the Food and Agricultural Organization (FAO), where foreign ministers from the three countries discussed the financial crisis confronting the United Nations Relief and Works Agency for Palestinian Refugees (UNRWA).
"We consider this as a very important first step in the collective effort and mobilization to close this year's critical funding shortfall", UNRWA Commissioner-General Pierre Krahenbuhl told a press conference.
The United Nations Secretary General António Guterres will travel for London to attend the conference and co-chair a ministerial meeting of the International Support Group for Lebanon.
"If UNRWA would not exist, if these services were not provided, the security of region would be severely undermined", Guterres told reporters.
Cutting sanitation, health care and medical services in already poverty-wracked and conflict-ridden areas "would have severe impacts a cascade of problems that could push the suffering in disastrous and unpredictable directions", he warned.More news: Ford looks to topple Toyota hybrids, Jeep SUVs in brand overhaul
Speaking to Al Jazeera from Rome, Christopher Gunness, senior spokesperson for UNRWA, said they had started with a 2018 budget deficit of $446m - and although pledges for funding were made, there is "work to do on the funding".
The move came after US President Donald Trump threatened on January 3 to cut aid to the agency, which serves more than five million people.
The U.S. had been UNWRA's largest donor, supplying almost 30 percent of its budget. But the agency said the actual cut was around $300 million because the USA had led the agency to believe it would provide $365 million in 2018.
Founded in 1949 to provide help to Palestinian refugees in the Middle East, UNRWA now supports some 5.3 million people.
He stressed the support of UNRWA is a political message that the worldwide community has not abandoned the Palestinian refugees and has not left them victims of destitution and despair, and will not contribute to depriving half a million students of their right to decent living and education in the five areas of UNRWA work. The country contributed $6 billion in humanitarian aid in 2016 while the US contributed $6.3 billion, DI data shows.