The US State Department said Washington has so far provided $887 million in direct health and humanitarian assistance to combat the outbreak, making it the largest donor to the response.

The aid announcement, made on the sidelines of the UN General Assembly, also seeks to "call on capable nations to increase burden sharing to meet the urgency of the moment," the statement said.

Outgoing UN Secretary-General Antonio Guterres last month issued an appeal to raise an additional $1.1 billion in aid against the epidemic, which continues to spread to new parts of the DRC, according to the NGO Doctors Without Borders (MSF).

The Ebola outbreak has killed more than 3,600 people and infected 7,500 since mid-May, according to Congolese public health officials, making it the DRC's worst recorded epidemic of the disease.