The outbreak has reached 1,495 cases and 984 deaths, including 406 cases and 308 deaths in April.
"WHO and partners cannot tackle these challenges without the international community stepping in" to provide funds.
Today's 26 deaths mark the deadliest day of the outbreak, and 15 of them took place in the community.
As deaths hit 900, the illness total edged within striking distance of 1,400.
The outbreak totals now stand at 1,373 cases, including 890 deaths.
The Democratic Republic of the Congo (DRC) health ministry today reported another double-digit rise in Ebola cases, raising the overall total to 1,353 illnesses, according to its daily update.
The 13 cases are all from current epicenters: Katwa (5), Vuhovi (4), and 1 each in Butembo, Mabalako, Masereka, and Beni. Also, health officials are still investigating 68 suspected cases.
The outbreak has grown to 1,340 cases and 874 deaths.
Amid a violent attack on outbreak responders, the outbreak total climbed to 1,317 with the addition of 15 new cases.
Cases have now topped 1,300 and include 843 deaths, with no signs of slowing.
Traditional chiefs and local officials took new steps to ease community resistance to response efforts.
